CN104004942A - TiC particle-reinforced nickel-based composite material and preparation method thereof - Google Patents

Abstract

The invention provides a TiC particle-reinforced nickel-based composite material, which is characterized in that the components and percentages contained in the material are: the volume percentage of TiC particles is 3%-30%, and the rest is master alloy; the master alloy The alloy is one of all nickel alloys; the method uses prefabricated block green body Ni-Ti-C as particle synthesis reactant, wherein the composition of the synthesis reactant is Ni powder, Ti powder and C powder, and the quality of Ni powder is 100%. The TiC powder content is 5-50%, the molar ratio of Ti powder and C powder is 1:1, and the prefabricated block green body and master alloy are added into a vacuum induction furnace for melting to prepare TiC particle reinforced composite material. The invention effectively solves the traditional problems of high preparation cost, complex process, various particle shapes, uneven distribution, and poor density, and has the characteristics of low cost and simple process, and the method can be used to manufacture large and complex nickel-based superalloys. casting.

Description

A kind of TiC particle reinforced nickel-based composite material and preparation method thereof

technical field

The invention relates to the field of composite materials, in particular to a TiC particle-reinforced nickel-based composite material and a preparation method thereof.

Background technique

Due to its excellent high-temperature performance, nickel-based superalloys have become the main materials for manufacturing advanced aero-engines and gas turbine hot-end components, mainly including casing-like load-bearing parts, turbine blades, combustion chambers, turbine disks, and some compressor blades. The rapid development of aerospace technology requires complex parts of aircraft to withstand higher operating temperatures. The development of nickel-based high-temperature composite materials with higher heat-resistant temperatures is crucial to improving the thermal efficiency of engines, which can reduce fuel consumption and improve engine performance. , improve the flight range of the aircraft, and have the effect of energy saving and emission reduction. Therefore, there is an urgent need for cast nickel-based superalloy materials with higher service temperature.

At present, the heat-resistant temperature of the common K4169 cast nickel-based alloy is 650 °C. When it exceeds 650 °C, its main high-temperature strengthening phase γ’’ will dissolve or transform into δ phase, losing the high-temperature strengthening effect. At present, at home and abroad, the high-temperature performance of nickel-based alloys is mainly improved by adding a large amount of scarce precious metals such as Co, W, and Re. However, the present invention improves the high-temperature performance of the material by adding low-cost second phase reinforcement particles to prepare nickel-based composite materials.

Particle-reinforced composites can effectively improve the wear resistance and high-temperature performance of basic alloy materials, and the particle-reinforced method is widely used to prepare metal matrix composites. Lu Weijie from Shanghai Jiaotong University and others prepared titanium-based composite materials using TiC, TiB and rare earth oxides as strengthening phases (patent publication numbers ZL02111575.3, ZL02112260.1 and ZL200510029075.3, etc.). There are many reports on the preparation of aluminum matrix composites using particle reinforcement. A method for preparing particle reinforced aluminum matrix composites invented by Mi Guofa et al. (ZL201210413996.x), and a method invented by Wang Hongming et al. Methods for synthesizing particle-reinforced composite materials (ZL201110037708.0), etc. Wang Huiyuan of Jilin University and others added TiC particles to magnesium alloys and steels to improve the wear resistance of the alloys through the in situ autogenous method. Due to the limitation of the performance of the matrix material, the high-temperature performance of magnesium-based, aluminum-based, titanium-based and iron-based composite materials has always been unable to surpass that of nickel-based superalloy materials.

There are many patents and literatures on the preparation of metal matrix composites by particle reinforcement, but there are few literatures on the preparation of nickel-based alloy composites by TiC particle reinforcement. Representative ones include Zhang Xinghong from Harbin Institute of Technology and others who used self-propagating high-temperature combustion synthesis (SHS) combined with hot isostatic pressing to prepare TiC-Ni-based cermet materials. This method is limited by technical equipment and can only prepare composite materials with low Ni content. material, if the Ni content exceeds 70%, the SHS synthesis reaction cannot occur. Because the raw materials of this preparation technology are all powders, which need to be pressed and formed, it is difficult to prepare workpieces with complex shapes, and the density of the finished product is far lower than that of workpieces prepared by casting technology, and the production cost of this technology is high. Bao Yanrong of North China Electric Power University and others published an article on metal heat treatment "The microstructure and properties of in-situ synthesis of TiC-xNi composite materials by hot pressing", which introduced a method of preparing nickel-based composite materials by powder metallurgy, but The workpiece prepared by powder metallurgy has certain limitations on the shape of the finished product and the density of the material. In addition, Liu Zongde and others from North China Electric Power University published an article on the in-situ self-generation method for the preparation of nickel-based composites on "Materials Science and Engineering A". The process of this method is: firstly, the mixed powder of Ti and C is pressed into a prefabricated block , and then Ti-C prefabricated blocks and electrolytic nickel were heated and smelted in a vacuum induction furnace to prepare TiC particle-reinforced nickel-based composite materials. The results showed that the distribution of TiC particles in the ingot was uneven, and the particle shapes were square and needle-like. , the properties of TiC particle reinforced nickel-based composites prepared by this process are not stable. In addition, the TiC particle-reinforced nickel-based composite particle preparation raw material is a binary system composed of Ti powder and C powder. The synthesis reaction temperature of the Ti-C binary system is high, and the melting point of the high-temperature metal Ni is close to the melting point of Ti. , is not conducive to particle size control and uniform distribution. Liu Zongde and others also invented a preparation method for in-situ reaction synthesis of TiC _x particle-reinforced nickel-based composites (ZL200910091602.1). In this method, the mixed powder of Ti, C, Al, Fe and Mo is wrapped with nickel foil, pressed After forming a block, put it into a vacuum medium-frequency induction furnace, melt and cast it together with electrolytic nickel, and prepare a TiC _x particle-reinforced nickel-based composite material with a density close to 100% and a significantly improved high-temperature strength and hardness. The nickel matrix used in this process is mainly metallic nickel powder, which is expensive, and the mixed powder needs to be wrapped with nickel foil and pressed into blocks. The process is complex and not suitable for industrialized mass production.

Contents of the invention

In view of the defects in the prior art, the object of the present invention is to provide a TiC particle reinforced nickel-based composite material and its preparation method, which has simple process and low cost, and can control the size and quantity of TiC particles in the composite material.

According to one aspect of the present invention, there is provided a TiC particle-reinforced nickel-based composite material, the components and contents of which are: the TiC particle volume percentage is 3%-30%, and the rest is a master alloy; the master alloy The alloy is one of all nickel alloys.

Preferably, the TiC particles are produced by reacting a Ni-Ti-C prefabricated block green body, the composition of the Ni-Ti-C prefabricated block green body is Ni powder, Ti powder and C powder, and the mass percentage of Ni powder is 5 -50%, the molar ratio of Ti powder to C powder is 1:1. More preferably, the mass percentage of Ni powder is 20-30%.

Preferably, the Ni powder has a particle size of 200-800 mesh and a purity of ≥99.5%.

Preferably, the particle size of the Ti powder is 200-800 mesh, and the purity is ≥99.5%.

Preferably, the C powder has a particle size of ≤2000 mesh and a purity of ≥99.5%.

Preferably, the volume percentage of the TiC particles is 3-10%, further, 4-7%. Within this range, a TiC particle-reinforced nickel-based composite material with better performance can be obtained.

Preferably, the size of the TiC particles is less than 10 microns, more preferably, the size of the TiC particles is less than 5 microns.

Preferably, the shape of the TiC particles is equiaxed, spherical or cubic, more preferably spherical.

According to another aspect of the present invention, there is provided a method for preparing the above-mentioned TiC particle-reinforced nickel-based composite material. The method uses prefabricated block green body (Ni-Ti-C) as a particle synthesis reactant, and adds it together with the master alloy to Melting and preparing TiC particle-reinforced composite materials in a vacuum induction furnace specifically includes the following steps:

(1) Weigh Ni powder, Ti powder, C powder and master alloy according to the mass percentage of each component;

⑵Use mixing equipment to mix the powder with good ratio in step ⑴ evenly;

(3) Pressing the uniformly mixed powder in step (2) into a Ni-Ti-C prefabricated block green body;

(4) Put the green prefabricated block and the master alloy together into a vacuum induction furnace for melting and casting into an ingot.

Preferably, in the step (2): Ni powder, Ti powder and C powder are uniformly mixed using a mixing method such as a mixer, a mixer or a ball mill.

Preferably, in the step (3): cold isostatic pressing is used to prepare the mixed powder into a Ni-Ti-C prefabricated block green body, and the compaction density of the green body is 50-90%.

More preferably, in the step (3): put the uniformly mixed powder in the step (2) into the mold, apply a pressure of 50-100 MPa, and pressurize for 10-20 seconds, and prepare a Ni-Ti-C prefabricated block green body , and its density is 50-90%.

Preferably, the step (4) is specifically as follows:

①Sample loading: put the prepared prefabricated block green body and master alloy together into a vacuum induction furnace for melting;

②Smelting atmosphere: the vacuum degree in the furnace is evacuated to 1×10 ^-2 -1×10 ^-4 Pa, and argon gas is introduced to make the pressure 0.01-0.08MPa,

③Smelting and casting: raise the temperature in the furnace to 1450-1800°C, refine for 3-8 minutes, and then cast into ingots to obtain the TiC particle-reinforced nickel-based composite material.

The method of the invention uses the prefabricated block green body (Ni-Ti-C system) as a reactant, melts it together with the nickel-based master alloy, and successfully prepares the TiC particle-reinforced nickel-based composite material. The green prefabricated block is heated to the reaction temperature by vacuum induction, and TiC particles with regular shape (spherical), reasonable size (<10 μm) and clean interface with the matrix are synthesized, and the TiC particles are evenly distributed in the base alloy by induction stirring. This technology effectively solves the problems of traditional TiC particle-reinforced nickel-based composite materials, such as high preparation cost, complex process, various particle shapes, uneven distribution, and poor density. The invention adopts the process of combining the in-situ synthesis method with the traditional smelting and casting, and is a low-cost and simple process for preparing TiC particle reinforced nickel-based composite materials, and the method can be used to manufacture large-scale complex castings of nickel-based superalloys. The invention can control the particle size, shape and quantity in the composite material by adjusting the composition of the in-situ synthesis reactant (Ni-Ti-C prefabricated block green body).

Compared with the prior art, the present invention has the following beneficial effects:

① The present invention does not wrap the mixed powder with nickel foil, and can prepare a high-performance nickel-based composite material through a simple and low-cost method;

②The spherical TiC particles prepared by the present invention have regular appearance, reasonable size and uniform distribution;

③ The present invention can adjust the addition amount of the prefabricated block green body to control the content of reinforcement in the composite material (3%-30%), so as to prepare nickel-based composite materials with different performances to meet different needs;

④ The present invention can produce products with high density, large size and complex shape because it is smelted and casted.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention. Parts that are not described in detail in the following embodiments can be implemented using existing technologies.

Example 1: Preparation of a nickel-based composite material with a volume percentage of TiC of 3%

① Preparation of mixed powder: Weigh nickel powder (purity: 99.5%, particle size: -200 mesh), titanium powder (purity: 99.5%, particle size: -200 mesh) and C powder (purity: 99.5%, particle size: -12500 order), Ni powder 50wt.%, the mol ratio of Ti powder and C powder is 1:1, three kinds of powders are mixed homogeneously with self-made mixer;

②Green body preparation: put the mixed powder into a mold with an inner diameter of Ф50mm, apply a pressure of 100MPa for 20 seconds, and prepare a green prefabricated block of Ф50mm×10mm with a density of 90%;

③Smelting and casting: Put the prefabricated block of the green body and the K4169 master alloy into a vacuum induction melting furnace, and the mass percentage of the green body and the K4169 master alloy is about 1:55. The vacuum in the furnace was evacuated to 1×10 ^-4 Pa, and argon was introduced to make the pressure 0.01MPa. Start smelting, the temperature in the furnace rises to 1450°C, and cast into ingots after refining for 3 minutes;

In this embodiment, 50% Ni-Ti-C system reacts to synthesize spherical TiC particles with a size of about 3 μm, and the particles are uniformly distributed in the base alloy, and the volume percentage thereof accounts for about 3%.

Example 2: Preparation of a nickel-based composite material with a volume percentage of TiC of 5%

① Preparation of mixed powder: Weigh nickel powder (purity: 99.5%, particle size: -400 mesh), titanium powder (purity: 99.5%, particle size: -400 mesh) and C powder (purity: 99.5%, particle size: -8000 order), Ni powder 10wt.%, the mol ratio of Ti powder and C powder is 1:1, three kinds of powders are mixed with mixer;

②Green body preparation: put the mixed powder into a mold with an inner diameter of Ф50mm, apply a pressure of 80MPa for 15 seconds, and prepare a green prefabricated block of Ф50mm×12mm with a density of 70%;

③Smelting and casting: Put the prefabricated block of the green body and the K4169 master alloy into the vacuum induction melting furnace, and the mass percentage of the green body and the K4169 master alloy is about 1:26. The vacuum in the furnace was evacuated to 0.6×10 ^-3 Pa, and argon gas was introduced to make the pressure 0.04MPa. Start smelting, the temperature in the furnace rises to 1650°C, and cast into ingots after 5 minutes of refining;

In this embodiment, 10% Ni-Ti-C system reacts to synthesize spherical TiC particles with a size less than 8 μm, and the particles are uniformly distributed in the base alloy, and its volume percentage accounts for about 5%.

Example 3: Preparation of a nickel-based composite material with a volume percentage of TiC particles of 15%

① Preparation of mixed powder: Weigh nickel powder (purity: 99.5%, particle size: -400 mesh), titanium powder (purity: 99.5%, particle size: -400 mesh) and C powder (purity: 99.5%, particle size: -8000 order), Ni powder 20wt.%, the mol ratio of Ti powder and C powder is 1:1, three kinds of powders are mixed with mixer;

②Green body preparation: put the mixed powder into a mold with an inner diameter of Ф50mm, apply a pressure of 75MPa for 15 seconds, and prepare a green prefabricated block of Ф50mm×13mm with a density of 65%;

③Smelting and casting: Put the prefabricated block of the green body and the K4202 master alloy into a vacuum induction melting furnace, and the mass percentage of the green body and the K4202 master alloy is about 1:7.5. The vacuum in the furnace was evacuated to 0.6×10 ^-3 Pa, and argon gas was introduced to make the pressure 0.04MPa. Start smelting, the temperature in the furnace rises to 1650°C, and cast into ingots after 5 minutes of refining;

In this embodiment, 20% Ni-Ti-C system reacts to synthesize spherical TiC particles with a size less than 8 μm, and the particles are uniformly distributed in the K4202 base alloy, and its volume percentage accounts for about 15%.

Example 4: Preparation of a nickel-based composite material with a volume percentage of TiC particles of 30%

① Preparation of mixed powder: Weigh nickel powder (purity: 99.5%, particle size: -800 mesh), titanium powder (purity: 99.5%, particle size: -800 mesh) and C powder (purity: 99.5%, particle size: -2000 order), Ni powder 5wt.%, the mol ratio of Ti powder and C powder is 1:1, three kinds of powders are mixed with ball mill;

②Green body preparation: put the mixed powder into a mold with an inner diameter of Ф50mm, apply a pressure of 50MPa for 10 seconds, and prepare a green prefabricated block of Ф50mm×15mm with a density of 50%;

③Smelting and casting: Put the prefabricated block of the green body and the K4169 master alloy into a vacuum induction melting furnace, and the mass percentage of the green body and the K4169 master alloy is about 1:36. The vacuum in the furnace was evacuated to 1×10 ^-2 Pa, and argon was introduced to make the pressure 0.08MPa. Start smelting, the temperature in the furnace rises to 1800°C, and cast into ingots after 8 minutes of refining;

In this embodiment, 5% Ni-Ti-C system reacts to synthesize spherical TiC particles with a size less than 10 μm, and the particles are uniformly distributed in the base alloy, and its volume percentage accounts for about 30%.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims (14)

1. A TiC particle-reinforced nickel-based composite material is characterized in that, the components and percentages contained in the material are: the volume percentage of TiC particles is 3%-30%, and the rest are master alloys; The alloy is one of all nickel alloys. 2. TiC particle reinforced nickel-based composite material according to claim 1, is characterized in that, described TiC particle is to generate by Ni-Ti-C prefabricated block green body reaction, the composition of Ni-Ti-C prefabricated block green body It is Ni powder, Ti powder and C powder, the mass percentage of Ni powder is 5-50%, and the molar ratio of Ti powder and C powder is 1:1. 3. The TiC particle-reinforced nickel-based composite material according to claim 2, characterized in that the mass percentage of the Ni powder is 20-30%. 4. The TiC particle-reinforced nickel-based composite material according to claim 2, characterized in that, the particle size of the Ni powder is 200-800 mesh, and the purity is ≥99.5%; the particle size of the Ti powder is 200-800 mesh, Purity ≥ 99.5%; the C powder has a particle size ≤ 2000 mesh and a purity ≥ 99.5%. 5. The TiC particle-reinforced nickel-based composite material according to any one of claims 1-4, characterized in that the TiC particle volume percentage is 3-10%. 6. The TiC particle-reinforced nickel-based composite material according to claim 5, characterized in that the size of the TiC particles is less than 10 microns. 7. The TiC particle-reinforced nickel-based composite material according to claim 6, characterized in that the size of the TiC particles is less than 5 microns. 8. The TiC particle-reinforced nickel-based composite material according to any one of claims 1-4, wherein the shape of the TiC particles is equiaxed, spherical or cubic. 9. The TiC particle-reinforced nickel-based composite material according to claim 8, characterized in that the shape of the TiC particle is spherical. 10. A method for preparing TiC particle reinforced nickel-based composite material according to any one of claims 1-9, characterized in that, the method uses prefabricated block green body Ni-Ti-C as particle synthesis reactant, Adding it together with the master alloy into a vacuum induction furnace for smelting to prepare a TiC particle-reinforced composite material; specifically includes the following steps: (1) Weigh Ni powder, Ti powder, C powder and master alloy according to the mass percentage of each component; ⑵Use mixing equipment to mix the powder with good ratio in step ⑴ evenly; (3) Pressing the uniformly mixed powder in step (2) into a Ni-Ti-C prefabricated block green body; (4) Putting the Ni-Ti-C prefabricated block green body and the master alloy together into a vacuum induction furnace to melt and cast it into an ingot to obtain the composite material. 11. The preparation method of TiC particle-reinforced nickel-based composite material according to claim 10, characterized in that, in the step (2), Ni powder, Ti powder and C powder are uniformly mixed with a stirrer, a mixer or a ball mill. 12. The preparation method of TiC particle-reinforced nickel-based composite material according to claim 10, characterized in that, in said step (3): the mixed powder is prepared into a Ni-Ti-C prefabricated block by cold isostatic pressing The green compact of the Ni-Ti-C prefabricated block is pressed with a density of 50-90%. 13. The preparation method of TiC particle-reinforced nickel-based composite material according to claim 10, characterized in that, in the step (3): the powder mixed uniformly in the step (2) is packed into a mould, and a pressure of 50-100MPa is applied, The pressing time is 10-20 seconds, and the Ni-Ti-C prefabricated block green body is prepared, and its density is 50-90%. 14. The preparation method of the TiC particle reinforced nickel-based composite material according to any one of claims 10-13, wherein the step (4) is specifically as follows: ①Sample loading: put the prepared prefabricated block green body and master alloy together into a vacuum induction furnace for melting; ②Smelting atmosphere: the vacuum degree in the furnace is evacuated to 1×10 ^-2 -1×10 ^-4 Pa, and argon gas is introduced to make the pressure 0.01-0.08MPa, ③Smelting and casting: raise the temperature in the furnace to 1450-1800°C, refine for 3-8 minutes, and then cast into ingots to obtain the TiC particle-reinforced nickel-based composite material.