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CN117965963B - High-performance engine valve and preparation process thereof - Google Patents

High-performance engine valve and preparation process thereof Download PDF

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Publication number
CN117965963B
CN117965963B CN202410383739.9A CN202410383739A CN117965963B CN 117965963 B CN117965963 B CN 117965963B CN 202410383739 A CN202410383739 A CN 202410383739A CN 117965963 B CN117965963 B CN 117965963B
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valve
powder
cladding
pure
alloy
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CN117965963A (en
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钱智敏
钱朝辉
陈汉平
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Yancheng Xiaoyu Machinery Co ltd
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Yancheng Xiaoyu Machinery Co ltd
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/055—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 20% but less than 30%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting
    • C22C1/023—Alloys based on nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting
    • C22C1/03—Making non-ferrous alloys by melting using master alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/007—Alloys based on nickel or cobalt with a light metal (alkali metal Li, Na, K, Rb, Cs; earth alkali metal Be, Mg, Ca, Sr, Ba, Al Ga, Ge, Ti) or B, Si, Zr, Hf, Sc, Y, lanthanides, actinides, as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C24/00—Coating starting from inorganic powder
    • C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
    • C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
    • C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
    • F01L3/02—Selecting particular materials for valve-members or valve-seats; Valve-members or valve-seats composed of two or more materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
    • F01L3/02—Selecting particular materials for valve-members or valve-seats; Valve-members or valve-seats composed of two or more materials
    • F01L3/04—Coated valve members or valve-seats

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Powder Metallurgy (AREA)

Abstract

The invention discloses a high-performance engine valve and a preparation process thereof, wherein the valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, and the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight, wherein the balance of Ni and unavoidable impurities is ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.27~0.58%;Al 2.15~4.33%;Y 0.08~0.24%;Ti 1.15~3.10%;Ce 0.12~0.35%;. The engine valve provided by the invention has excellent mechanical strength, high temperature resistance, high temperature oxidation resistance and high temperature corrosion resistance.

Description

High-performance engine valve and preparation process thereof
Technical Field
The invention relates to the field of engine parts, in particular to a high-performance engine valve and a preparation process thereof.
Background
The valve is specially responsible for inputting air into the engine and exhausting combusted exhaust gas. From the engine structure, it is divided into an intake valve (INTAKE VALVE) and an exhaust valve (exhaust valve). The air intake valve is used for sucking air into the engine and mixing the air with fuel for combustion; the exhaust valve is used for exhausting and radiating the burnt exhaust gas.
The valve is in a high working environment temperature (the inlet valve 570-670K and the exhaust valve 1050-1200K), ions with stronger corrosivity such as CO 3 2-、SO4 2-, cl - and the like are usually generated when fuel is combusted, and meanwhile, the valve also bears the pressure of gas, the acting force of a valve spring and the inertia force of a transmission component, and the valve is required to have enough strength, heat resistance, wear resistance, high-temperature oxidation resistance, overlooking resistance and the like in the severe working environment.
The nickel-based superalloy has high strength and good oxidation resistance and gas corrosion resistance, and is often used as valve materials, such as conventional alloys of Inconel751, nimonic80A and the like. In order to further improve the overall performance of the valve, in the prior art, alloy components are usually optimized or new reinforcing components are added, for example, patent CN103451559 a-a valve alloy material and a manufacturing method thereof, CN 108193142B-a high-hardness alloy valve and a manufacturing method thereof, CN 114134428A-a nickel-saving iron-based superalloy for an engine valve and a manufacturing method thereof, and the like. Nb, ti, and the like can be added to the alloy as reinforcing elements, but differences in melting point, density, thermal expansion coefficient, and the like of the elements cause that these elements are likely to be unevenly dispersed in the alloy, and it is difficult to sufficiently exert their reinforcing effects. On the other hand, in order to cope with the severe working environment of the valve, the high-temperature oxidation resistance and strength of the valve surface still need to be further improved so as to prolong the service life of the valve.
Therefore, there is a need in the art for improvements that provide a more reliable solution.
Disclosure of Invention
The invention aims to solve the technical problem of providing a high-performance engine valve and a preparation process thereof aiming at the defects in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme: the high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight, and the balance of ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.27~0.58%;Al 2.15~4.33%;Y 0.08~0.24%;Ti 1.15~3.10%;Ce 0.12~0.35%; is Ni and unavoidable impurities.
Preferably, the chemical components of the high-temperature-resistant nickel-based alloy valve matrix comprise ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.34~0.51%;Al 2.63~3.87%;Y 0.11~0.17%;Ti 1.45~2.14%;Ce 0.18~0.27%; parts by weight of Ni and unavoidable impurities in balance.
Preferably, the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.46%; al 3.51%; y0.15%; ti 1.94%; ce 0.24%; the balance being Ni and unavoidable impurities.
The invention also provides a preparation process of the high-performance engine valve, which comprises the following steps of:
S1, smelting:
Weighing raw materials of the high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: smelting pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe, pure Ni and intermediate alloy;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging;
s3, annealing;
s4, hot upsetting to prepare a valve blank;
S5, heat treatment;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
S7, finishing to obtain a high-performance engine valve finished product.
Preferably, the preparation process of the high-performance engine valve comprises the following steps of:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 5-10Pa, and smelting at 1500-1650 ℃ for 10-20min;
S1-2, then filling argon of 0.05-0.1Pa, adding intermediate alloy, and continuing smelting for 5-12min at 1500-1650 ℃;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging:
pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1450-1550 ℃; then heating the valve alloy ingot to 1120-1180 ℃, and cogging and forging by a 2000-4000 ton oil press, wherein the forging temperature is 1140-1150 ℃, and the final forging temperature is 950-1000 ℃, so as to forge a valve blank;
S3, annealing: annealing the valve blank for 0.5-2h under the vacuum condition at 650-750 ℃, and cooling along with a furnace;
S4, hot upsetting to prepare a valve blank: heating the annealed valve blank to 900-1100 ℃, and hot upsetting into a valve blank in a die;
S5, heat treatment: heating the valve blank to 950-1050 ℃, carrying out heat preservation and solution treatment for 1-2 h, and cooling to room temperature; then preserving heat and aging for 4-8 hours at 600-680 ℃, and performing air cooling to room temperature and then machining to obtain a valve primary product;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
s7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product.
Preferably, the preparation process of the high-performance engine valve comprises the following steps of:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
S1-2, then filling argon of 0.08Pa, adding intermediate alloy, and continuing smelting for 6min at 1550 ℃;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging:
pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge a valve blank;
s3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with a furnace;
s4, hot upsetting to prepare a valve blank: heating the annealed valve blank to 1050 ℃, and hot upsetting into a valve blank in a die;
s5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain a valve primary product;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
s7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product.
Preferably, the master alloy is prepared by the following method:
Adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace according to the mass percent of each element, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained master alloy melt into a mould to obtain the master alloy.
Preferably, the chemical components of the master alloy comprise, in weight percent: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance being Ni and unavoidable impurities.
Preferably, the step S6 specifically includes:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of each element, namely, si to Ti to C, wherein Zr=1 (2.1-2.4), 0.4-0.8, 1.55-1.9 and 0.65-0.95, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
S6-2, uniformly mixing the cladding powder and the organic binder according to the mass ratio of 10:1-10:2.5, then placing for 30-60min, uniformly coating the surface of the valve blank after heat treatment, wherein the thickness of the coating layer is 1-1.5mm, naturally airing for 10-16h, and then drying for 4-8h at 150-180 ℃;
S6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4-6.5mm, controlling the cladding current to be 120-128A, the cladding voltage to be 17-21V, the cladding speed to be 0.08-0.15m/min and the argon gas flow to be 5-10L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
Preferably, the step S6 specifically includes:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing the cladding powder and the organic binder according to the mass ratio of 10:1.5, then standing for 45min, uniformly coating the surface of the valve blank after heat treatment, naturally airing for 12h, and then drying for 6h at 170 ℃;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
The beneficial effects of the invention are as follows:
According to the invention, by optimizing the components of the nickel-based alloy valve matrix and matching with the surface enhanced cladding process, the high-performance engine valve product with excellent mechanical strength, high temperature resistance, high temperature oxidation resistance and high temperature corrosion resistance can be obtained, the application environment requirements of the valve can be well met, and the valve has a wide application prospect.
The part of the reinforcing element Nb, al, Y, ti, ce in the invention is added into the raw material through forming an intermediate alloy with Ni, and the main functions of the element include: (1) Nb, Y, ce, ti and other elements, such as melting point, density, thermal expansion coefficient and the like, so that the elements are easy to disperse unevenly in the alloy, and particularly for a trace amount of Nb, Y and Ce, the uneven in the alloy structure greatly influences the exertion of the reinforcing effect; according to the invention, nb, al, Y, ti, ce and part of Ni are smelted to form the intermediate alloy with pre-dispersed microelements, and a large amount of Ni3 (Al, ti, nb) gamma 'phases can be formed in advance in the process, the main element in the intermediate alloy is Ni, so that the effect similar to that of coating other microelements by Ni is formed, good compatibility between the intermediate alloy and other raw materials can be ensured, and uniform dispersion of Nb, Y, ce and other elements in the whole alloy matrix can be promoted, and higher-content gamma' phases can be formed;
(2) Nb, al and Y are easily oxidized elements, oxidation caused by external environment in the smelting process is reduced, the enhancement effect of the alloy matrix can be improved, and the easily oxidized elements, ni and Ce with certain deoxidizing capability form an intermediate alloy in advance, so that oxidation caused by external environment of Nb, al and Y in the smelting process can be reduced.
The invention further takes Mo, si, ti, C, zr as a raw material, and forms the reinforced cladding layer on the surface of the valve through surface cladding treatment, so that the surface strength, wear resistance, high-temperature oxidation resistance and high-temperature corrosion resistance of the valve can be further improved.
Drawings
FIG. 1 is a flow chart of a process for preparing a high performance engine valve of the present invention;
FIG. 2 is a graph showing the hardness distribution of the reinforcing cladding layer in example 1 of the present invention;
FIG. 3 shows the results of the oxidation resistance test in the present invention.
Detailed Description
The present invention is described in further detail below with reference to examples to enable those skilled in the art to practice the same by referring to the description.
It will be understood that terms, such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.
The test methods used in the following examples are conventional methods unless otherwise specified. The material reagents and the like used in the following examples are commercially available unless otherwise specified. The following examples were conducted under conventional conditions or conditions recommended by the manufacturer, without specifying the specific conditions. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
The invention provides a high-performance engine valve, which comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight, the balance of ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.27~0.58%;Al 2.15~4.33%;Y 0.08~0.24%;Ti 1.15~3.10%;Ce 0.12~0.35%; being Ni and unavoidable impurities.
In a preferred embodiment, the chemical composition of the high temperature resistant nickel-based alloy valve substrate comprises ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.34~0.51%;Al 2.63~3.87%;Y 0.11~0.17%;Ti 1.45~2.14%;Ce 0.18~0.27%; percent by weight of Ni and unavoidable impurities as the balance.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 5-10Pa, and smelting at 1500-1650 ℃ for 10-20min;
S1-2, then filling argon of 0.05-0.1Pa, adding intermediate alloy, and continuing smelting for 5-12min at 1500-1650 ℃;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
wherein, the intermediate alloy is prepared by the following method:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1450-1550 ℃; then heating the valve alloy ingot to 1120-1180 ℃, and cogging and forging by a 2000-4000 ton oil press, wherein the forging temperature is 1140-1150 ℃, and the final forging temperature is 950-1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 0.5-2h under the vacuum condition at 650-750 ℃ and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: heating the annealed valve blank to 900-1100 ℃, and hot upsetting into a valve blank in a die.
S5, heat treatment: heating the valve blank to 950-1050 ℃, carrying out heat preservation and solution treatment for 1-2 h, and cooling to room temperature; then heat preservation aging treatment is carried out for 4-8 hours at 600-680 ℃, and the valve primary product is obtained after air cooling to room temperature and machining.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of each element, namely, si to Ti to C, wherein Zr=1 (2.1-2.4), 0.4-0.8, 1.55-1.9 and 0.65-0.95, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
S6-2, uniformly mixing the cladding powder and the organic binder according to the mass ratio of 10:1-10:2.5, then placing for 30-60min, uniformly coating the surface of the valve blank after heat treatment, wherein the thickness of the coating layer is 1-1.5mm, naturally airing for 10-16h, and then drying for 4-8h at 150-180 ℃;
S6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4-6.5mm, controlling the cladding current to be 120-128A, the cladding voltage to be 17-21V, the cladding speed to be 0.08-0.15m/min and the argon gas flow to be 5-10L/min, and forming a reinforced cladding layer on the surface of the valve substrate after finishing the surface cladding treatment to obtain a valve coarse product.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product.
1. The main chemical composition design principle and the process principle of the high-temperature-resistant nickel-based alloy valve matrix are described below to facilitate the understanding of the invention.
In a preferred embodiment, the high temperature nickel-base alloy valve matrix comprises the following chemical components in percentage by weight ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.34~0.51%;Al 2.63~3.87%;Y 0.11~0.17%;Ti 1.45~2.14%;Ce 0.18~0.27%;
C can form carbide with Cr, nb, ti and the like, can improve mechanical properties, strengthen grain boundaries, and can improve strength and hot workability to a certain extent, but can lose plasticity, and the content thereof should be strictly controlled, and is preferably 0.04-0.11%.
Si can improve the oxidation resistance, gas corrosion resistance and other performances of the alloy, but can have adverse effect on plasticity, and the content of the Si is preferably 0.35-0.52% in the invention, so that a better effect can be obtained.
Cr can improve the high-temperature corrosion resistance and high-temperature oxidation resistance and the thermal strength of the alloy; cr can stabilize ferrite and reduce an austenite region, but excessive Cr content can lead to dispersion and precipitation of alpha-Cr and reduce the strength of steel, and the content of the Cr is preferably controlled to be 17.62-22.53 percent in the invention.
The Mo atoms have large radius, and after solid solution, the crystal lattice is greatly distorted, so that the alloy matrix can be obviously strengthened, and the high-temperature strength and red hardness of the matrix are improved. Mo can obviously improve the lattice mismatch degree of gamma and gamma' in the alloy, promote the establishment of a two-phase interface dislocation network, and simultaneously, the addition of Mo can also reduce the stacking fault energy, thereby improving the creep property of the alloy.
Cu can effectively improve the gas-resistant corrosion resistance, and Fe is added to replace part of Ni to reduce the cost of alloy materials. Ni is a main alloy element, so that the alloy obtains a gamma matrix with a face-centered cubic structure, and can form Ni3 (Al, ti) intermetallic compounds, namely gamma' phases with Al and Ti, thereby greatly improving the corrosion resistance and the high temperature resistance of the alloy material.
The addition of Al and Ti can form a gamma' phase with Ni, which strengthens the action of the matrix; al can improve the oxidation resistance of the alloy, and an Al 2O3 film with good protection property can be formed on the surface of the alloy. Ti can form high-strength carbide TiC with C in the matrix, thereby improving the strength of the alloy. At higher titanium and aluminum contents, titanium also forms eta phase Ni 3 Ti with nickel, and the constituent phase with hexagonal structure does not dissolve other elements, which can make the steel brittle. Therefore, the Ti content is preferably 1.45 to 2.14% in the present invention.
Nb can play roles in refining grains, improving plasticity and the like, can strengthen carbide formation (the carbide of Nb is quite stable at high temperature), and improves the high-temperature strength, hardness and wear resistance of the alloy; at the same time, nb is able to enter the γ' phase, forming a Ni3 (Al, ti, nb) reinforcement phase.
Y has the functions of grain refinement, solid solution strengthening, dispersion strengthening and the like, trace yttrium can improve the oxidation resistance of the nickel-based alloy, Y can form stable Y 2O3 oxide with oxygen in the alloy, and the problem of oxygen embrittlement at a grain boundary can be solved by stabilizing the oxygen.
Ce can promote heterogeneous nucleation, refine grains, and improve the strength, toughness and corrosion resistance of the alloy; and Ce is easy to oxidize, can react with oxygen in the alloy to form cerium oxide with high melting point, and can play a role in deoxidization.
The other reinforcing elements Nb, al, Y, ti, ce in the invention are added to the raw material by forming an intermediate alloy with Ni, and the main functions of the reinforcing elements include: (1) Nb, Y, ce, ti and other elements, such as melting point, density, thermal expansion coefficient and the like, so that the elements are easy to disperse unevenly in the alloy, and particularly for a trace amount of Nb, Y and Ce, the uneven in the alloy structure greatly influences the exertion of the reinforcing effect; according to the invention, nb, al, Y, ti, ce and part of Ni are smelted to form the intermediate alloy with pre-dispersed microelements, and a large amount of Ni3 (Al, ti, nb) gamma 'phases can be formed in advance in the process, the main element in the intermediate alloy is Ni, so that the effect similar to that of coating other microelements by Ni is formed, good compatibility between the intermediate alloy and other raw materials can be ensured, and even dispersion of Nb, Y, ce and other elements in the whole alloy matrix can be promoted, and higher-content gamma' phases can be formed.
(2) Nb, al and Y are easily oxidized elements, oxidation caused by external environment in the smelting process is reduced, the enhancement effect of the alloy matrix can be improved, and the easily oxidized elements, ni and Ce with certain deoxidizing capability form an intermediate alloy in advance, so that oxidation caused by external environment of Nb, al and Y in the smelting process can be reduced.
2. The principle of designing the main chemical components of the reinforcing cladding layer is explained below to facilitate the understanding of the present invention.
According to the invention, mo, si, ti, C, zr is used as a raw material, and the reinforced cladding layer is formed on the surface of the valve through surface cladding treatment, so that the surface strength, wear resistance, high-temperature oxidation resistance and high-temperature corrosion resistance of the valve can be further improved. The reinforced cladding layer is a MoSi 2 -SiC-TiC-ZrC composite system cladding layer formed by the alloy powder under the high-temperature action of an electric arc, wherein a basic phase MoSi 2 is a Darton type intermetallic compound, and the composite system cladding layer has excellent high-temperature oxidation resistance and strength; it still has some drawbacks: such as low-temperature brittleness, low-temperature oxidation pulverization, lower high-temperature strength, and the like; the hardness and the wear resistance of SiC formed by Si and C can be improved, and C in a matrix at an interface can also participate in forming SiC, so that the interface bonding strength can be improved.
Ti has higher affinity to O than Si, and can form a compact oxide layer on the surface, so that low-temperature oxidation pulverization can be inhibited to a certain extent; and TiC phase formed by Ti and C can improve the high-temperature strength and corrosion resistance of the cladding layer.
Zr can enter the lattice structure of MoSi 2 to form Mo-Si-Zr-O phase at lattice defect, which can inhibit low temperature oxidation of MoSi 2; meanwhile, zr and C can form a ZrC phase with high strength, and the high-temperature strength of the cladding layer can be remarkably improved. Zr and Ni in the matrix have better compatibility, and are beneficial to improving interface strength.
Under the action of high temperature, zirconium in the cladding layer at the boundary can enter a gamma 'phase in the matrix, so that the gamma' phase of the interface accessory is reinforced, and the interface connection strength is improved; y, ce in the matrix at the boundary enters the cladding layer, so that the spalling resistance of the coating can be improved, and the strength between the interfaces can be improved.
The foregoing is a general inventive concept and the following detailed examples and comparative examples are provided on the basis thereof to further illustrate the invention.
Example 1
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.46%; al 3.51%; y0.15%; ti 1.94%; ce 0.24%; the balance being Ni and unavoidable impurities.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
s1-2, then filling argon of 0.08Pa, adding intermediate alloy (accounting for about 20% of the total raw material mass), and continuing smelting at 1550 ℃ for 6min;
Wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance of Ni and unavoidable impurities;
The intermediate alloy is prepared by the following steps:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; and then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: and heating the annealed valve blank to 1050 ℃, and hot upsetting the valve blank in a die.
S5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; and then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain the valve primary product.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product. In this example, test pieces for tensile properties were prepared in the same manner.
Example 2
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.41%; al 3.16%; y0.14%; ti 1.75%; ce 0.22%; the balance being Ni and unavoidable impurities.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
s1-2, then filling argon of 0.08Pa, adding intermediate alloy (accounting for about 18% of the total raw material mass), and continuing smelting at 1550 ℃ for 6min;
Wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance of Ni and unavoidable impurities;
The intermediate alloy is prepared by the following steps:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; and then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: and heating the annealed valve blank to 1050 ℃, and hot upsetting the valve blank in a die.
S5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; and then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain the valve primary product.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product. In this example, test pieces for tensile properties were prepared in the same manner.
Example 3
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.35%; al 2.63%; y0.11%; ti 1.46%; ce 0.18%; the balance being Ni and unavoidable impurities.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
s1-2, then filling argon of 0.08Pa, adding intermediate alloy (accounting for about 15% of the total raw material mass), and continuing smelting at 1550 ℃ for 6min;
Wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance of Ni and unavoidable impurities;
The intermediate alloy is prepared by the following steps:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; and then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: and heating the annealed valve blank to 1050 ℃, and hot upsetting the valve blank in a die.
S5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; and then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain the valve primary product.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product. In this example, test pieces for tensile properties were prepared in the same manner.
Example 4
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.51%; al 3.86%; y0.17%; ti 2.13%; ce 0.26%; the balance being Ni and unavoidable impurities.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
s1-2, then filling argon of 0.08Pa, adding intermediate alloy (accounting for about 22% of the total raw material mass), and continuing smelting at 1550 ℃ for 6min;
Wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance of Ni and unavoidable impurities;
The intermediate alloy is prepared by the following steps:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; and then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: and heating the annealed valve blank to 1050 ℃, and hot upsetting the valve blank in a die.
S5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; and then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain the valve primary product.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product. In this example, test pieces for tensile properties were prepared in the same manner.
Example 5
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises the following chemical components in percentage by weight: c0.07%; si 0.45%; cr 20.9%; mo 1.12%; cu 4.4%; fe 13.2%; nb 0.46%; al 3.51%; y0.15%; ti 1.94%; ce 0.24%; the balance being Ni and unavoidable impurities.
The preparation process of the high-performance engine valve comprises the following steps:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
s1-2, then filling argon of 0.08Pa, adding intermediate alloy (accounting for about 20% of the total raw material mass), and continuing smelting at 1550 ℃ for 6min;
Wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance of Ni and unavoidable impurities;
The intermediate alloy is prepared by the following steps:
according to the mass percentage of each element, adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
S2, pouring and forging:
Pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; and then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge the valve blank.
S3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with the furnace.
S4, hot upsetting to prepare a valve blank: and heating the annealed valve blank to 1050 ℃, and hot upsetting the valve blank in a die.
S5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; and then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain the valve primary product.
S6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
S7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product. In this example, test specimens for tensile properties were prepared in the same manner; the following comparative examples were also prepared simultaneously with the test specimens.
Comparative example 1
This example is substantially the same as example 1, except that:
the intermediate alloy of the example comprises the following chemical components in percentage by weight: nb 2.30%; 17.55% of Al; ti 9.70%; the balance being Ni and unavoidable impurities.
The intermediate alloy is prepared by the following steps:
Adding Ni powder, nb powder, al powder and Ti powder into a crucible in a vacuum smelting furnace according to the mass percent of each element, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained intermediate alloy melt into a die to obtain the intermediate alloy.
Comparative example 2
The present example is basically the same as the embodiment 1, except for the step S6, in which the step S6 specifically includes:
S6-1, mixing Mo powder, si powder, ti powder and graphite powder according to the mass percent of Mo to Ti and C=1:2.35:0.6:1.75, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
Comparative example 3
The present example is basically the same as the embodiment 1, except for the step S6, in which the step S6 specifically includes:
s6-1, mixing Mo powder, si powder, graphite powder and Zr powder according to the mass percent of Mo to Si to C, wherein Zr=1:2.35:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing cladding powder and an organic binder (PAVL liquid glue) according to a mass ratio of 10:1.5, then placing for 45min, uniformly coating the mixture on the surface of a valve blank after heat treatment, naturally airing for 12h, and then drying at 170 ℃ for 6h;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
Comparative example 4
The high-performance engine valve comprises a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the chemical components of the high-temperature-resistant nickel-based alloy valve matrix are as shown in the following table 1 according to the formula of an Inconel751 nickel-based alloy:
TABLE 1
C Si Mn Cr Nb Ti Al Fe Ni
Chemical composition% 0.06 0.11 0.23 15.41 0.91 2.34 1.35 6.26 Bal.
The specific preparation process is the same as in example 1.
1. Mechanical properties at different temperatures
Tensile test samples prepared in examples 1 to 5 and comparative examples 1 to 4 were subjected to tensile test with reference to the standard GB/T15012-2009 "Nickel-based superalloy and Nickel-based superalloy tensile test method", and the test results are shown in Table 2 below:
TABLE 2
From the test results of table 2, it can be seen that the high temperature resistant nickel-based alloy valve materials prepared in examples 1 to 5 have excellent high temperature strength and are due to the conventional Inconel751 alloy material.
2. The surface hardness (valve cone) of example 1, comparative examples 1-3 was measured, and the test results are shown in table 3 below; and the hardness distribution of the reinforcing cladding layer in example 1 was tested using a micro vickers hardness tester, and the hardness distribution is shown in fig. 2.
TABLE 3 Table 3
Example 1 Comparative example 1 Comparative example 2 Comparative example 3
Hardness HV 0.5 1135 1131 984 1007
From the test results, it can be seen that the hardness of the reinforcing cladding layer of example 1 can reach 1135HV 0.5, which is higher than that of comparative examples 2 and 3, and is comparable to that of comparative example 1.
3. Test of antioxidant Properties
The valve finished products prepared in example 1 and comparative examples 1 to 5 were subjected to oxidation resistance test with reference to Standard HB5288-83 "method for measuring oxidation resistance of Steel and alloy: and (3) carrying out constant-temperature oxidation experiments in a box-type electric furnace, wherein the experimental temperature is 1000 ℃, placing the valve finished product sample into a quartz crucible with a pre-fired constant weight, and ensuring that the sample is in point contact with the crucible wall. After oxidation for a certain time (2, 4,6,8, 10, 12h respectively), the crucible was taken out and weighed on an electronic balance, and the oxidation increment Δm of the reinforcing cladding layer per unit area was calculated according to the following formula:
The unit is mg/cm 2;
Wherein M0 represents the initial sample weight, mt represents the sample weight at time t, and S represents the area of the reinforcing cladding layer in cm 2.
As shown in fig. 3, it can be seen from the test results that the oxidation increment Δm gradually increases with the increase of the oxidation time, and the increase of example 1 is the lowest and the high-temperature oxidation resistance is the strongest.
Although embodiments of the present invention have been disclosed above, it is not limited to the use of the description and embodiments, it is well suited to various fields of use for the invention, and further modifications may be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the particular details without departing from the general concepts defined in the claims and the equivalents thereof.

Claims (8)

1. The high-performance engine valve is characterized by comprising a high-temperature-resistant nickel-based alloy valve matrix and a reinforced cladding layer arranged on the surface of the valve matrix, wherein the high-temperature-resistant nickel-based alloy valve matrix comprises ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.27~0.58%;Al 2.15~4.33%;Y 0.08~0.24%;Ti 1.15~3.10%;Ce 0.12~0.35%; of Ni and unavoidable impurities in balance by weight percent;
the preparation process of the high-performance engine valve comprises the following steps of:
S1, smelting:
Weighing raw materials of the high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: smelting pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe, pure Ni and intermediate alloy;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging;
s3, annealing;
s4, hot upsetting to prepare a valve blank;
S5, heat treatment;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
s7, finishing to obtain a high-performance engine valve finished product;
The step S6 specifically comprises the following steps:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of each element, namely, si to Ti to C, wherein Zr=1 (2.1-2.4), 0.4-0.8, 1.55-1.9 and 0.65-0.95, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
S6-2, uniformly mixing the cladding powder and the organic binder according to the mass ratio of 10:1-10:2.5, then placing for 30-60min, uniformly coating the surface of the valve blank after heat treatment, wherein the thickness of the coating layer is 1-1.5mm, naturally airing for 10-16h, and then drying for 4-8h at 150-180 ℃;
S6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4-6.5mm, controlling the cladding current to be 120-128A, the cladding voltage to be 17-21V, the cladding speed to be 0.08-0.15m/min and the argon gas flow to be 5-10L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
2. The high performance engine valve of claim 1, wherein the high temperature nickel-base alloy valve base body comprises, in weight percent, ：C 0.04~0.11%;Si 0.35~0.52%;Cr 17.62~22.53%;Mo 0.70~1.33%;Cu 3.41~6.75%;Fe 14.24~18.68%;Nb 0.34~0.51%;Al 2.63~3.87%;Y 0.11~0.17%;Ti 1.45~2.14%;Ce 0.18~0.27%; balance Ni and unavoidable impurities.
3. The high performance engine valve of claim 2, wherein the high temperature resistant nickel-based alloy valve base comprises, in weight percent: c0.08%; si 0.42%; cr 21.4%; mo 0.95%; cu 4.8%; fe 16.7%; nb 0.46%; al 3.51%; y0.15%; ti 1.94%; ce 0.24%; the balance being Ni and unavoidable impurities.
4. The high performance engine valve of claim 1, wherein the process for preparing the high performance engine valve comprises the steps of:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 5-10Pa, and smelting at 1500-1650 ℃ for 10-20min;
S1-2, then filling argon of 0.05-0.1Pa, adding intermediate alloy, and continuing smelting for 5-12min at 1500-1650 ℃;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging:
pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1450-1550 ℃; then heating the valve alloy ingot to 1120-1180 ℃, and cogging and forging by a 2000-4000 ton oil press, wherein the forging temperature is 1140-1150 ℃, and the final forging temperature is 950-1000 ℃, so as to forge a valve blank;
S3, annealing: annealing the valve blank for 0.5-2h under the vacuum condition at 650-750 ℃, and cooling along with a furnace;
S4, hot upsetting to prepare a valve blank: heating the annealed valve blank to 900-1100 ℃, and hot upsetting into a valve blank in a die;
S5, heat treatment: heating the valve blank to 950-1050 ℃, carrying out heat preservation and solution treatment for 1-2 h, and cooling to room temperature; then preserving heat and aging for 4-8 hours at 600-680 ℃, and performing air cooling to room temperature and then machining to obtain a valve primary product;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
s7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product.
5. The high performance engine valve of claim 4, wherein the process for preparing the high performance engine valve comprises the steps of:
S1, smelting:
S1-1, weighing raw materials of a high-temperature-resistant nickel-based alloy valve matrix according to the mass percentage ratio of each element: adding pure graphite, pure Si, pure Cr, pure Mo, pure Cu, pure Fe and pure Ni into a vacuum induction smelting furnace, vacuumizing to 7.5Pa, and smelting for 15min at 1600 ℃;
S1-2, then filling argon of 0.08Pa, adding intermediate alloy, and continuing smelting for 6min at 1550 ℃;
wherein the chemical components of the intermediate alloy comprise the following components in percentage by weight:
Nb 2.11-2.84%; 15.26-19.31% of Al; y is 0.57-0.88%; 8.55-10.92% of Ti; ce 0.94-1.36%; the balance of Ni and unavoidable impurities;
s2, pouring and forging:
pouring the alloy melt obtained in the step S1 to obtain a valve alloy ingot, wherein the pouring temperature is 1480 ℃; then heating the valve alloy ingot to 1150 ℃, and forging by a 4000 ton oil press, wherein the forging temperature is 1140 ℃, and the final forging temperature is 1000 ℃, so as to forge a valve blank;
s3, annealing: annealing the valve blank for 1h under vacuum condition at 700 ℃, and cooling along with a furnace;
s4, hot upsetting to prepare a valve blank: heating the annealed valve blank to 1050 ℃, and hot upsetting into a valve blank in a die;
s5, heat treatment: heating the valve blank to 1000 ℃, carrying out heat preservation and solution treatment for 1h, and cooling to room temperature; then preserving heat and aging for 6 hours at 650 ℃, and carrying out air cooling to room temperature and then machining to obtain a valve primary product;
s6, carrying out surface cladding treatment on the valve blank after heat treatment to form a reinforced cladding layer on the surface of the valve matrix, so as to obtain a valve coarse product;
s7, finishing the reinforced cladding layer to the required size to obtain a high-performance engine valve finished product.
6. The high performance engine valve of claim 4 or 5, wherein the master alloy is prepared by:
Adding Ni powder, nb powder, al powder, Y powder, ti powder and Ce powder into a crucible in a vacuum smelting furnace according to the mass percent of each element, vacuumizing to 0.25Pa, smelting for 7min at 1520 ℃, and pouring the obtained master alloy melt into a mould to obtain the master alloy.
7. The high performance engine valve of claim 6, wherein the chemical composition of the master alloy comprises, in weight percent: nb 2.30%; 17.55% of Al; y0.75%; ti 9.70%; ce 1.20%; the balance being Ni and unavoidable impurities.
8. The high performance engine valve according to claim 1, wherein the step S6 is specifically:
S6-1, mixing Mo powder, si powder, ti powder, graphite powder and Zr powder according to the mass percent of Mo to Ti to C, wherein Zr=1:2.35:0.6:1.75:0.8, and ball milling for 6 hours under the protection of argon to obtain cladding powder;
s6-2, uniformly mixing the cladding powder and the organic binder according to the mass ratio of 10:1.5, then standing for 45min, uniformly coating the surface of the valve blank after heat treatment, naturally airing for 12h, and then drying for 6h at 170 ℃;
s6-3, cladding the surface of the coating layer by using an electric arc of argon tungsten-arc welding, controlling the distance between the tungsten electrode and the coating layer to be 4.5mm, controlling the cladding current to be 125A, the cladding voltage to be 19.5V, the cladding speed to be 0.12m/min and the argon gas flow to be 8L/min, and obtaining a valve crude product after finishing the surface cladding treatment.
CN202410383739.9A 2024-04-01 2024-04-01 High-performance engine valve and preparation process thereof Active CN117965963B (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106498234A (en) * 2016-11-01 2017-03-15 河钢股份有限公司 Continuously extruded die cavity plug material of a kind of combination type and preparation method thereof
CN113718134A (en) * 2020-05-22 2021-11-30 日本制铁株式会社 Ni-based alloy pipe and welded joint

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7486925B2 (en) * 2019-04-02 2024-05-20 日本製鉄株式会社 Alloy Tube
CN114645162A (en) * 2022-03-11 2022-06-21 中国航发北京航空材料研究院 A kind of manufacturing method of fine-grained homogeneous disk forging of hard-to-deform superalloy
CN116065057A (en) * 2022-12-12 2023-05-05 成都先进金属材料产业技术研究院股份有限公司 High-quality high-temperature alloy bar for aerospace and subjected to high W-Mo solid solution strengthening and preparation method thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106498234A (en) * 2016-11-01 2017-03-15 河钢股份有限公司 Continuously extruded die cavity plug material of a kind of combination type and preparation method thereof
CN113718134A (en) * 2020-05-22 2021-11-30 日本制铁株式会社 Ni-based alloy pipe and welded joint

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