CN118527955A - Method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive - Google Patents

Abstract

The present invention provides a method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing, which relates to the technical field of heat-resistant aluminum alloys. S1: a milling machine is used to perform surface flattening treatment on a 6061 aluminum alloy substrate, and then the oil stain on the surface of the 6061 aluminum alloy substrate is cleaned with acetone; S2: the 6061 substrate is fixed on a workbench of a friction stir deposition device modified by a self-developed machining center, and a friction deposition rod of a specific component is installed at a specified position of the device; S3: a hydraulic system is used to drive the specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and the specific friction deposition rod is rotated and rubbed along the surface of the 6061 substrate to advance, and the specific friction deposition rod and the 6061 substrate are deposited under the action of thermal coupling, and a high-strength heat-resistant aluminum alloy is prepared by reciprocating multi-layer deposition. The manufacturing process is simple, safe, and more convenient to operate, and the alloy produced has high strength and high temperature resistance.

Description

Friction stir deposition additive manufacturing method for binary Al-Ce heat-resistant alloy

Technical Field

The invention relates to the technical field of heat-resistant aluminum alloys, and in particular to a method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing.

Background Art

Heat-resistant aluminum alloys have been widely used in aerospace, automobile, shipbuilding, weapons and other industries, mainly due to their advantages of high specific strength, low density, and good oxidation resistance. However, the existing high-temperature performance of heat-resistant aluminum alloys is close to the limit state. After the working temperature exceeds 200°C, its mechanical properties are significantly reduced, which makes it difficult to meet the demand for use temperature and has great safety hazards. Therefore, the development of new heat-resistant aluminum alloys with excellent room temperature performance, good oxidation resistance and fatigue resistance, and good heat resistance and high-temperature stability is of great significance to the automotive industry, aerospace and other application fields.

Additive manufacturing technology based on solidification molding significantly improves the service temperature and performance of alloys compared to traditional processing technologies. However, solidification defects (pores, cracks, etc.) generated during the solidification process of the alloy have an adverse effect on the mechanical properties. Friction stir deposition (AFSD) is a solid additive method. During the additive manufacturing process, the alloy will undergo severe plastic deformation at high temperatures, undergo dynamic recrystallization, and then form a uniform fine-grained microstructure. In addition, compared with other additive manufacturing methods based on solidification molding, it also has the advantages of low requirements for the working environment and simple raw material processing.

Summary of the invention

The purpose of the present invention is to provide a method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing, which solves the problem of mechanical properties of the binary Al-Ce heat-resistant alloy at room temperature and high temperature.

The above technical objectives of the present invention are achieved through the following technical solutions:

A method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing comprises the following steps:

S1: Use a milling machine to smooth the surface of the 6061 aluminum alloy substrate, and then use acetone to clean the oil stains on the surface of the 6061 aluminum alloy substrate;

S2: Fix the 6061 substrate on the workbench of the stir friction deposition equipment modified by the self-developed machining center, and install the friction deposition rod of specific composition at the specified position of the equipment;

S3: A hydraulic system is used to drive the specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and to rotate and rub along the surface of the 6061 substrate. Deposition occurs between the specific friction deposition rod and the 6061 substrate under the action of thermal coupling, and a high-strength and heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

According to the method for manufacturing binary Al-Ce heat resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the optimized process parameters in S2 are:

The thickness of a single-layer deposition layer of the specific friction deposition rod is 2 mm, the rotation speed is 200-300 rpm, the moving speed is 150-350 mm/min, and the feeding speed is 90-160 mm/min.

According to the method for stir friction deposition additive manufacturing of binary Al-Ce heat-resistant alloy provided by the present invention, the preparation process of the friction deposition rod with specific components in S3 is a casting and hot extrusion process, and the preparation raw materials are metal aluminum and Al-Ce master alloy.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the preparation steps of the friction deposition rod with specific components in S3 are as follows:

S3.1: Selecting aluminum and Al-Ce master alloy;

S3.2: preheating the alloy raw material metal aluminum and Al-Ce master alloy;

S3.3: heating and melting the preheated metal aluminum and Al-Ce master alloy to obtain a first alloy melt; the heating and melting temperature is 850-900°C;

S3.4: adding the preheated Al-Ce alloy to the obtained first alloy melt and then smelting to obtain an Al-Ce melt; the smelting temperature is 790-810° C.;

S3.5: Casting the Al-Ce melt, and then cooling it to room temperature to obtain an alloy ingot.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the steps of hot extrusion of the alloy ingot made of S3.5 are as follows:

S3.5.1: The extrusion die size is a square die of 10 x 10 mm, the extrusion temperature is 440-450 ° C, the die temperature is 440-450 ° C, and the outlet temperature is not required (measured and recorded), and the air is cooled to room temperature for straightening. The final size of the friction deposition rod is 10 x 10 x 200 mm.

S3.5.2: After the hot extrusion process, the required stir friction deposition additive manufacturing rod is obtained.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the substrate has a thickness of 10 to 20 mm, a width of 100 to 200 mm, and a length of 200 to 300 mm.

In summary, the beneficial technical effects of the present invention are:

(1) The Al-Ce alloy was prepared by friction stir deposition additive manufacturing technology, which significantly improved the morphology of the Al ₁₁ Ce ₃ phase in the alloy and refined the α-Al structure. The broken Al ₁₁ Ce ₃ phase particles were evenly distributed on the matrix, which alleviated the stress concentration and made the pinning dislocation effect more significant, thereby improving the room temperature and high temperature tensile strength of the alloy.

(2) When using stir friction deposition additive technology to prepare Al-Ce alloy, the overall operation process is simpler, and the process is safe, reliable and easy to operate, so it can be better implemented and popularized, and more quickly applied to various production processes.

Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a comparison diagram of the microstructure of a binary Al-Ce heat-resistant alloy manufactured by friction stir deposition additive manufacturing in Example 1 of the present invention;

FIG2 is a comparison diagram of the fracture morphology of a binary Al-Ce heat-resistant alloy manufactured by friction stir deposition additive manufacturing in Example 1 of the present invention;

FIG3 is a comparison diagram of grain sizes of binary Al-Ce heat-resistant alloys manufactured by friction stir deposition additive manufacturing in Example 1 of the present invention;

FIG4 is a comparison of room temperature and high temperature tensile properties data of a binary Al-Ce heat-resistant alloy manufactured by friction stir deposition additive manufacturing in Example 1 of the present invention.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms are not directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

The technical solution of the present invention is described below in conjunction with the embodiments shown in Figures 1 to 4:

A binary Al-Ce heat-resistant alloy comprises the following components calculated by mass percentage: Ce: 11.5-12.5%, and the balance Al; the phase composition of the binary Al-Ce heat-resistant alloy comprises: Al ₁₁ Ce ₃ phase and α-Al phase; in the phase composition of the binary Al-Ce heat-resistant alloy, the α-Al phase is refined, and the grain size is less than 10 microns.

In the present invention, the Ce element can form Al ₁₁ Ce ₃ phase with Al. This phase hardly decomposes when the temperature is close to the eutectic temperature, has good heat resistance, and is beneficial to improving the heat resistance of the alloy.

The purity of the selected metallic aluminum and Al-Ce master alloy is preferably 99.9% or above independently. There is no special limitation on the sources of the metallic aluminum and Al-Ce master alloy. Commercially available products familiar to those skilled in the art can be used. The metallic aluminum is preferably industrial pure aluminum ingots; the Al-Ce master alloy is preferably Al-20Ce master alloy.

A method for preparing a binary high-strength and heat-resistant Al-Ce alloy by friction stir deposition technology, the steps are as follows:

S1: Use a milling machine to smooth the surface of the 6061 aluminum alloy substrate, and then use acetone to clean the oil stains on the surface of the 6061 aluminum alloy substrate;

S2: Fix the 6061 substrate on the workbench of the stir friction deposition equipment modified by the self-developed machining center, and install the friction deposition rod of specific composition at the specified position of the equipment;

S3: A hydraulic system is used to drive the specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and to rotate and rub along the surface of the 6061 substrate. Deposition occurs between the specific friction deposition rod and the 6061 substrate under the action of thermal coupling, and a high-strength and heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

According to the method for manufacturing binary Al-Ce heat resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the optimized process parameters in S2 are:

The thickness of a single-layer deposition layer of the specific friction deposition rod is 2 mm, the rotation speed is 200-300 rpm, the moving speed is 150-350 mm/min, and the feeding speed is 90-160 mm/min.

According to the method for stir friction deposition additive manufacturing of binary Al-Ce heat-resistant alloy provided by the present invention, the preparation process of the friction deposition rod with specific components in S3 is a casting and hot extrusion process, and the preparation raw materials are metal aluminum and Al-Ce master alloy.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the preparation steps of the friction deposition rod with specific components in S3 are as follows:

S3.1: Selecting aluminum and Al-Ce master alloy;

S3.2: preheating the alloy raw material metal aluminum and Al-Ce master alloy;

S3.3: heating and melting the preheated metal aluminum and Al-Ce master alloy to obtain a first alloy melt; the heating and melting temperature is 850-900°C;

S3.4: adding the preheated Al-Ce alloy to the obtained first alloy melt and then smelting to obtain an Al-Ce melt; the smelting temperature is 790-810° C.;

S3.5: Casting the Al-Ce melt, and then cooling it to room temperature to obtain an alloy ingot.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the steps of hot extrusion of the alloy ingot made of S3.5 are as follows:

S3.5.1: The extrusion die size is a square die of 10x10mm, the extrusion temperature is 440-450℃, the die temperature is 440-450℃, and there is no rigid requirement for the outlet temperature (measure and record), and the air is cooled to room temperature for straightening. The final friction deposition rod size is 10x10x200mm.

S3.5.2: After the hot extrusion process, the required stir friction deposition additive manufacturing rod is obtained.

According to the method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention, the substrate has a thickness of 10 to 20 mm, a width of 100 to 200 mm, and a length of 200 to 300 mm.

The method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing provided by the present invention has simple process, safety, reliability and convenient operation.

The above-mentioned preparation steps are further described below in the form of specific implementation methods, wherein the methods are conventional methods unless otherwise specified, and the raw materials can be obtained from public commercial channels or prepared according to literature unless otherwise specified.

Example 1

A binary Al-Ce heat-resistant alloy, composition (mass percentage): Ce: 11.5% and the balance Al;

A method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing, the specific steps are as follows:

Step 1: Before the experiment, preheat the metal aluminum and Al-Ce master alloy.

Step 2: Heat and melt the preheated metal aluminum and Al-Ce master alloy to obtain a first alloy melt, and the heating and melting temperature is 850°C.

Step 3: Add the preheated Al-Ce alloy to the obtained first alloy solution and then smelt to obtain an Al-Ce melt, and the smelting temperature is 790°C.

Step 4: Casting the Al-Ce melt, and then cooling it to room temperature to obtain an alloy ingot.

Step 5: hot extrude the alloy ingot, the extrusion die size is a square die of 10 x 10 mm, the extrusion temperature is 440°C, and after extrusion, the temperature is cooled to room temperature by blowing. The final friction deposition rod size is 10 x 10 x 200 mm.

Step 5: Use a milling machine to smooth the surface of the 6061 aluminum alloy substrate, and then use acetone to clean the oil stains on the surface of the 6061 aluminum alloy substrate.

Step 6: The substrate is selected to have a thickness of 10mm, a width of 100mm, and a length of 200mm.

Step 7: Fix the 6061 substrate on the workbench of the stir friction deposition equipment modified by the self-developed machining center.

Step 8: Install the friction deposition rod with specific composition in the specified position of the above equipment.

Step nine: A hydraulic system is used to drive a specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and the rod is rotated and rubbed along the surface of the 6061 substrate. Deposition occurs between the specific friction deposition rod and the 6061 substrate under the action of thermal coupling, and a high-strength and heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

Step 10: Optimize the process parameters, the single layer deposition thickness of the specific friction deposition rod is 2 mm, the rotation speed is 200-300 rpm, the moving speed is 150-350 mm/min, and the feed speed is 90-160 mm/min.

The Al-Ce heat-resistant alloy was analyzed for related structures. The microstructure comparison of the heat-resistant aluminum alloy is shown in Figure 1, the alloy fracture morphology comparison is shown in Figure 2, and the grain size comparison is shown in Figure 3. According to GB/T 228.1-2010 and GB/T 228.2-2015, the room temperature tensile strength of the alloy was 208Mpa, and the high temperature tensile strength at 300℃ was 70.61MPa. The comparison of room temperature and high temperature tensile test data is shown in Figure 4.

Example 2

A binary Al-Ce heat-resistant alloy, comprising (by mass%): 12% Ce and the balance Al;

A method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing, the specific steps are as follows:

Step 1: Before the experiment, preheat the metal aluminum and Al-Ce master alloy.

Step 2: Heat and melt the preheated metal aluminum and Al-Ce master alloy to obtain a first alloy melt, and the heating and melting temperature is 900°C.

Step 3: Add the preheated Al-Ce alloy to the obtained first alloy solution and then smelt to obtain an Al-Ce melt, and the smelting temperature is 800°C.

Step 4: Casting the Al-Ce melt, and then cooling it to room temperature to obtain an alloy ingot.

Step 5: hot extrude the alloy ingot, the extrusion die size is a square die of 10 x 10 mm, the extrusion temperature is 445°C, and after extrusion, the temperature is cooled to room temperature by blowing. The final friction deposition rod size is 10 x 10 x 200 mm.

Step 5: Use a milling machine to smooth the surface of the 6061 aluminum alloy substrate, and then use acetone to clean the oil stains on the surface of the 6061 aluminum alloy substrate.

Step 6: The substrate is selected to have a thickness of 10mm, a width of 100mm, and a length of 200mm.

Step 7: Fix the 6061 substrate on the workbench of the stir friction deposition equipment modified by the self-developed machining center.

Step 8: Install the friction deposition rod with specific composition in the specified position of the above equipment.

Step nine: A hydraulic system is used to drive a specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and the rod is rotated and rubbed along the surface of the 6061 substrate. Deposition occurs between the specific friction deposition rod and the 6061 substrate under the action of thermal coupling, and a high-strength and heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

Step 10: Optimize the process parameters, the single layer deposition thickness of the specific friction deposition rod is 2 mm, the rotation speed is 200-300 rpm, the moving speed is 150-350 mm/min, and the feed speed is 90-160 mm/min.

The manufactured Al-Ce heat-resistant alloy was tested according to GB/T 228.1-2010 and GB/T 228.2-2015, and the tensile strength of the alloy was measured to be 225 MPa at room temperature and 97.61 MPa at 300°C.

Example 3

A binary Al-Ce heat-resistant alloy, comprising (by mass%): 12.5% Ce and the balance Al;

A method for manufacturing a binary Al-Ce heat-resistant alloy by friction stir deposition additive manufacturing, the specific steps are as follows:

Step 1: Before the experiment, preheat the metal aluminum and Al-Ce master alloy.

Step 2: Heat and melt the preheated metal aluminum and Al-Ce master alloy to obtain a first alloy melt, and the heating and melting temperature is 900°C.

Step 3: Add the preheated Al-Ce alloy to the obtained first alloy solution and then smelt to obtain an Al-Ce melt, and the smelting temperature is 810°C.

Step 4: Casting the Al-Ce melt, and then cooling it to room temperature to obtain an alloy ingot.

Step 5: hot extrude the alloy ingot, the extrusion die size is a square die of 10 x 10 mm, the extrusion temperature is 450°C, and after extrusion, it is cooled to room temperature by blowing. The final friction deposition rod size is 10 x 10 x 200 mm.

Step 5: Use a milling machine to smooth the surface of the 6061 aluminum alloy substrate, and then use acetone to clean the oil stains on the surface of the 6061 aluminum alloy substrate.

Step 6: The substrate is selected to have a thickness of 10mm, a width of 100mm, and a length of 200mm.

Step 7: Fix the 6061 substrate on the workbench of the stir friction deposition equipment modified by the self-developed machining center.

Step 8: Install the friction deposition rod with specific composition in the specified position of the above equipment.

Step nine: A hydraulic system is used to drive a specific friction deposition rod to contact the 6061 substrate at a constant pressing speed, and the rod is rotated and rubbed along the surface of the 6061 substrate. Deposition occurs between the specific friction deposition rod and the 6061 substrate under the action of thermal coupling, and a high-strength and heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

Step 10: Optimize the process parameters, the single layer deposition thickness of the specific friction deposition rod is 2 mm, the rotation speed is 200-300 rpm, the moving speed is 150-350 mm/min, and the feed speed is 90-160 mm/min.

The manufactured Al-Ce heat-resistant alloy was tested according to GB/T 228.1-2010 and GB/T 228.2-2015, and the tensile strength of the alloy was measured to be 215.45 MPa at room temperature and 97.45 MPa at a high temperature of 300°C.

It can be seen from the above embodiments that the Al-Ce heat-resistant alloy provided by the present invention still has good tensile strength at high temperatures, and the value of the tensile strength is higher than the standard value specified in the relevant national standards.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (6)

1. A method for manufacturing binary Al-Ce heat-resistant alloy by friction stir deposition additive, which is characterized by comprising the following steps:

S1, carrying out surface leveling treatment on a 6061 aluminum alloy substrate by adopting a milling machine, and cleaning greasy dirt on the surface of the 6061 aluminum alloy substrate by using acetone;

s2, fixing a 6061 base plate on a friction stir deposition equipment workbench refitted by a self-grinding machining center, and installing a friction deposition rod with specific components at a designated position of the equipment;

and S3, driving the specific friction deposition rod to contact the 6061 substrate at a constant pressing speed by adopting a hydraulic system, and carrying out rotary friction advancing along the surface of the 6061 substrate, wherein the specific friction deposition rod and the 6061 substrate are deposited under the action of thermal coupling, and the high-strength heat-resistant aluminum alloy is prepared through reciprocating multi-layer deposition.

2. The method for friction stir deposition additive manufacturing of a binary Al-Ce heat resistant alloy of claim 1 wherein: and S2, optimizing the process parameters:

The thickness of the single-layer deposition layer of the specific friction deposition rod is 2mm, the rotating speed is 200-300rpm, the moving speed is 150-350mm/min, and the feeding speed is 90-160mm/min.

3. The method for friction stir deposition additive manufacturing of a binary Al-Ce heat resistant alloy of claim 1 wherein: the friction deposition rod with specific components in the S3 is prepared by casting and hot extrusion, and the preparation raw materials are metallic aluminum and Al-Ce intermediate alloy.

4. A method of friction stir deposition additive manufacturing a binary Al-Ce heat resistant alloy as recited in claim 3 in which: the preparation steps of the friction deposition rod with specific components in the step S3 are as follows:

s3.1: selecting metal aluminum and an Al-Ce intermediate alloy;

s3.2: preheating alloy raw material metal aluminum and A1-Ce intermediate alloy;

S3.3: heating and melting the preheated metal aluminum and the Al-Ce intermediate alloy to obtain a first alloy melt; the temperature of heating and melting is 850-900 ℃;

S3.4: adding preheated Al-Ce alloy into the obtained first alloy melt, and smelting to obtain an Al-Ce melt; the smelting temperature is 790-810 ℃;

s3.5: casting the Al-Ce melt, and then cooling to room temperature to obtain an alloy ingot.

5. The method for friction stir deposition additive manufacturing of a binary Al-Ce heat resistant alloy according to claim 4, wherein: the hot extrusion step of the alloy cast ingot made in S3.5 is as follows:

s3.5.1: the extrusion temperature of the square die with the extrusion die size of 10x 10mm is 440-450 ℃, the die temperature is 440-450 ℃, the temperature of a discharge hole is not required to be hard (measured and recorded), and the die is cooled to room temperature and straightened. The final shaped friction deposition bar size was 10x 200mm.

S3.5.2: and obtaining the required friction stir deposition additive manufactured bar after the hot extrusion process.

6. The method for friction stir deposition additive manufacturing of a binary Al-Ce heat resistant alloy of claim 1 wherein: the thickness of the substrate is 10-20 mm, the width is 100-200mm, and the length is 200-300mm.