CN108728695A - Multiphase nano ceramic particle hybrid reinforced nickel-based alloy and laser forming method thereof - Google Patents

Abstract

The invention provides a multi-phase nano-ceramic particle hybrid reinforced nickel-based alloy composite material and its laser forming method. The nickel-based superalloy is used as the matrix, and TiC, TiB ₂ and Al ₂ O ₃ with a particle size of 40-100 nm are used as the matrix. For the reinforcement phase, the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ added are 2.0-4.0%, 2.0-4.0%, and 1.0-3.0%, respectively. The invention has good performance advantages such as high-temperature corrosion resistance, wear resistance and high-temperature creep performance, and can meet the special performance requirements of the hot end parts of the aero-engine at high temperature. The method of the present invention can overcome the agglomeration effect brought by the huge surface energy of the nanoparticles, inhibit the agglomeration of the particles, and make the particles evenly distributed; at the same time, under the extremely fast solidification speed of the method of the present invention, the nanoparticle-reinforced phase can maintain its nanometer characteristics, so that the final The manufactured parts have excellent metallurgical bonding, high density, fine and dense microstructure, and excellent mechanical properties.

Description

A kind of multi-phase nano-ceramic particle hybrid reinforced nickel-based alloy and its laser forming method

technical field

The invention belongs to the field of nickel-based alloy preparation, and in particular relates to a multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy and a laser forming method thereof.

Background technique

Nickel-based superalloys have comprehensive properties such as high high-temperature strength, high-temperature creep strength, good fatigue performance, fracture toughness, good oxidation resistance and corrosion resistance, and it has good structural stability and reliability at high temperatures , occupies an important position in the entire superalloy field, and is widely used to manufacture the hottest parts of aviation jet engines and various industrial gas turbines.

Nickel-based superalloys are currently the most commonly used materials for the hot end of aero-engines. One of the most important performance parameters of an aero engine is the thrust-to-weight ratio. With the development of the aviation industry, modern aero-engines are constantly pursuing higher thrust-to-weight ratios. As the thrust-to-weight ratio increases, the turbine inlet temperature of high-performance aeroengines will inevitably increase, and it is increasingly important to solve the problem of heat resistance of engine hot-end parts materials. Research has shown that the combination of several cooling methods, coupled with heat-resistant coatings, can further increase the heat resistance of materials. But in general, the service temperature of nickel-based superalloys has reached 0.81T _m (Tm is the melting point of the material), which is approaching its limit. The potential for improving the thermal efficiency of aero-engines is very limited, and it cannot meet the engine service temperature. increasing demands.

Ceramic particle reinforced metal matrix composites have the advantages of high specific strength, specific modulus, high temperature resistance, small thermal expansion coefficient, wear resistance, corrosion resistance, good dimensional stability, etc., and have material designability. Among them, nanoparticle-reinforced metal matrix composites can maintain good toughness, high-temperature creep and fatigue resistance while improving mechanical properties such as strength and hardness. Various properties.

However, the preparation of nano-ceramic particle-reinforced nickel-based superalloys is much more complicated and difficult than micron-scale and sub-micron-scale. The main difficulties are: ① The surface energy generated by the huge specific surface area makes there be a strong agglomeration effect between nano-sized objects, and the density difference between the ceramic particles and the matrix metal is large, which is easy to cause agglomeration and reduce the impact of the reinforcing phase particles on the matrix metal. ② nano-ceramic particles reinforced metal matrix composites will inevitably undergo serious interface reactions when prepared at high temperature. The high melting point of ceramic materials and the low wettability and large linear expansion coefficient difference between the ceramic material and the matrix material will lead to interface Combine questions.

At present, the traditional processing methods of nano-ceramic particle reinforced nickel-based superalloys mainly include powder metallurgy, casting, spray deposition, and in-situ composite methods. In the powder metallurgy method, alloy powder and reinforced particles are uniformly mixed by high-energy ball milling, degassed, shaped, and then sintered into parts of the required shape. However, due to the huge surface energy and lattice distortion energy of nano-powders obtained by mechanical alloying, these energies are fully released during the long-term sintering process under the high temperature of traditional sintering methods, resulting in rapid grain growth, which is difficult to Maintain the size and characteristics of the original nanoparticles. At the same time, the powder metallurgy process is complicated, the production efficiency is low, the matrix metal is easy to oxidize, and it is difficult to uniformly disperse the nanoparticles and the matrix; the casting cannot take into account the uniformity and content of the ceramic reinforcement particles, the ceramic particles are easily segregated, and the performance of the formed parts is poor. , prone to casting defects.

Yan Hongge and others from Hunan University used the spray deposition method to form ceramic particle reinforced aluminum matrix composites (patent number CN 101775527 B), mixed the metal melt and ceramic reinforcement phase particles in the atomizer, and then atomized and sprayed onto the water-cooled substrate Forming on top. This method can effectively control the interfacial chemical reaction due to the extremely short contact time between the metal melt and the ceramic reinforcement phase particles, but there are also defects such as high porosity and large loss of raw materials.

Liu Zongde and others from North China Electric Power University synthesized TiCx particle-reinforced nickel-based composites by melting and casting in situ reaction (patent number CN 101649398 B). The in-situ composite method can well solve the wettability and interface problems between the reinforcement and the metal matrix, but the process is strict and difficult to master. It is difficult to control the composition and volume fraction of the reinforcement phase, and it is difficult to avoid other side reactions. presence of inclusions.

Zhang Xinghong from Harbin Institute of Technology and others 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 and is difficult to prepare. For workpieces with complex shapes, the density of the formed parts is low.

There are also Chinese patents "Method for preparing multi-element transition interface synergistically reinforced nickel-based composite material by 3D printing" CN201610197366.1, and "Method for preparing TiC-reinforced nickel-based composite material by selective laser melting forming method" CN201710288211.3, both based on Laser molding of nickel-based materials, but these two patents only add a kind of reinforcing particles and the size of the reinforcing particles is microns. Therefore, although laser molding is used, it still fails to solve the aforementioned problems of easy agglomeration and interfacial reactions of nanoparticles technical problem.

Contents of the invention

The purpose of the present invention is to overcome the defects in the prior art and provide a multi-phase nano-ceramic particle hybrid reinforced nickel-based alloy with excellent high-temperature performance and its laser forming method. The present invention improves the problems of particle agglomeration and interface bonding. The reinforced phase can maintain its nanometer characteristics, so that the final manufactured parts have excellent metallurgical bonding, high density, fine and compact microstructure, and excellent mechanical properties.

In order to achieve the above technical purpose, the technical solution of the present invention is: a multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy, using the nickel-based superalloy as the matrix, adding TiC, TiB ₂ and Al ₂ with a particle size of 40-100nm For O ₃ particle reinforcement phase, the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ are respectively 2.0-4.0%, 2.0-4.0%, and 1.0-3.0% of the multiphase nano-ceramic particle hybrid reinforced nickel-based superalloy.

Wherein, the nickel-based superalloy as the matrix is a regular spherical gas atomized powder with a particle size of 15-45 μm.

Wherein, according to the percentage by weight, the composition of the nickel-based superalloy as the matrix is: 21-23% Cr, 4-5% Fe, 0.1-0.4% Ti, 0.1-0.4% Al, 4-4.15% Nb, 8-10% Mo, 0.01-0.1% C and the balance Ni.

The present invention also provides a laser forming method for multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy. The multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy uses nickel-based superalloy as the matrix, and the added particle size is 40-100nm The TiC, TiB ₂ and Al ₂ O ₃ are reinforcing phases, and the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ added are respectively 2.0-4.0%, 2.0-4.0% and 2.0-4.0% of the multiphase nano-ceramic particle hybrid reinforced nickel-based superalloy. 4.0%, 1.0～3.0%;

The laser shaping method comprises the following steps:

(1) According to the performance requirements of the formed part, the TiC, TiB ₂ and Al ₂ O ₃ particles of the stated ratio are added to the nickel-based superalloy matrix to obtain a mixed powder;

(2) Under argon protection, use a ball mill to perform high-energy ball milling on the mixed powder in step (1) to obtain a uniformly mixed powder;

(3) Establish a three-dimensional CAD model of the part to be formed on the computer; use software to slice and layer the model to obtain a series of two-dimensional planes, and determine the laser scanning route; through the numerical control system, use the focused high-energy laser beam to perform step (2) The uniformly mixed powder in the machine is reciprocally scanned according to the determined scanning route, powder is spread layer by layer, fused and accumulated layer by layer, and superimposed layer by layer until a three-dimensional part is formed.

Wherein, the nickel-based superalloy as the matrix is a regular spherical gas atomized powder with a particle size of 15-45 μm.

Wherein, according to the percentage by weight, the composition of the nickel-based superalloy as the matrix is: 21-23% Cr, 4-5% Fe, 0.1-0.4% Ti, 0.1-0.4% Al, 4-4.15% Nb, 8-10% Mo, 0.01-0.1% C and the balance Ni.

Wherein, in the step (2), the ball-to-material ratio is 5:1-4:1, the ball-milling speed is 150-200 rpm, and the ball-milling time is 4-5 hours. Due to the high speed of the high-energy ball milling method, the output energy is enough to cause large plastic deformation of the powder and the crushing of the reinforcement phase particles. At the same time, the shape of the reinforcement phase particles and The uniformity of particle distribution of the reinforcement phase is improved.

Wherein, what used in the step (3) is a YLR-200 fiber laser with a maximum output power of 200W.

Wherein, in the step (3), the laser process parameters are as follows: the laser spot diameter is 70-100 μm, the laser power is 100-160 W, the laser scanning rate is 300-500 mm/s, and the laser scanning distance is 50-90 μm.

In the process of high-energy laser forming, firstly, the base plate of the forming cylinder is horizontally fixed on the platform, and the sealing device is filled with argon as a protective gas. Before powder application, the base plate of the forming cylinder is preheated with a high-energy laser beam. Then the automatic powder spreading device spreads the powder evenly on the base plate of the forming cylinder, the thickness of the powder spreading is 50-70 μm; then, the laser beam scans according to the set laser scanning route to make it melt and solidify quickly. The laser process parameters are as follows: the laser spot diameter is 70-100 μm, the laser power is 120-160 W, the laser scanning rate is 300-500 mm/s, and the laser scanning distance is 50-90 μm. Then repeat the steps of powder spreading and laser scanning, powder spreading layer by layer, fused and accumulated layer by layer, and superimposed layer by layer until a three-dimensional part is formed.

The present invention uses three kinds of reinforcing particles to reinforce synergistically and the size of the reinforcing particles is nanometer, which can further improve the comprehensive performance of the formed sample. TiC particles have the characteristics of high hardness, high melting point, good chemical stability, high modulus, and small difference in expansion coefficient with metals; adding Al ₂ O ₃ can make the composite material have excellent high temperature corrosion resistance. In addition, studies have shown that TiB+TiC hybrid reinforcement can improve the tensile strength and yield strength of the alloy. The hybrid reinforcement of various ceramic particles can take into account the characteristics of various reinforcements to make them complement each other, produce a hybrid effect, and improve or improve the performance of a single reinforcement material; nanoparticle-reinforced metal matrix composites can improve mechanical properties such as strength and hardness. At the same time, it maintains good toughness, high temperature creep and fatigue strength, so the performance of nickel-based superalloys can be significantly improved by mixing nano-TiB ₂ , TiC and Al ₂ O ₃ particles.

The invention adopts the following technical means: (1) ball milling and pre-mixing the powder before forming. During the forming process, the molten pool will generate agitation under the action of Marangoni convection, which can promote the rearrangement of particles, inhibit the agglomeration of particles, make the particles evenly distributed, and improve the uniformity of the structure; (2) Laser forming method is adopted. Due to the high energy of the laser, it can reach a very high working temperature, so that the mixed powder can be completely melted, and the problem of wettability and interface between the reinforced phase and the metal matrix can be solved; (3) The laser forming process is a process of rapid melting and solidification, The existence time of the liquid-phase molten pool is extremely short, and the cooling rate is as high as 10 ⁶ ～10 ⁸ K/s, and the crystal grains do not have enough time to grow up, which promotes the obvious refinement of the microstructure. Therefore, the present invention can overcome the agglomeration effect brought by the huge surface energy of nanoparticles, inhibit the agglomeration of particles, and make the particles evenly distributed; at the same time, the high-temperature melting and rapid solidification of laser molding can improve the wetting between the reinforcing phase and the metal matrix The nanoparticle-reinforced nickel-based alloy prepared by the present invention maintains the characteristics of nanoparticles, so that the final manufactured parts have excellent metallurgical bonding, high density, fine and compact microstructure, and excellent mechanical properties.

The beneficial effects of the present invention are:

1) Nano-TiC, TiB ₂ and Al ₂ O ₃ particle hybrid reinforced nickel-based superalloy composite material parts have good hardness, strength, tensile properties, high temperature corrosion resistance, wear resistance, high temperature creep properties and other properties Advantages, it can meet the special performance requirements of the hot end parts of the aero-engine at high temperature.

2) In the forming process of the present invention, under the action of Marangoni convection, the molten pool itself will generate agitation, promote the rearrangement of particles, inhibit the agglomeration of particles, make the particles evenly distributed, improve the uniformity of the structure, and make the reinforcing phase particles relatively stable to the matrix metal. The reinforcement effect is fully reflected.

3) The high-energy laser forming method used in the present invention is suitable for the preparation of difficult-to-machine materials and the forming of complex parts; without forming molds, the manufacturing cycle and cost are shortened; the liquid phase molten pool in the forming process has a short existence time and a high cooling rate. Due to the fast solidification speed, the crystal grains do not have time to grow up, and still maintain the characteristics of nanoparticles. The manufactured parts are fine, uniform, dense, and have excellent mechanical properties.

The invention can improve the problem of particle agglomeration and interface bonding, and at the same time, the nano particle reinforced phase can maintain its nanometer characteristics, so that the finally manufactured parts have excellent metallurgical bonding, high density, fine and compact microstructure, and excellent mechanical properties.

Description of drawings

Fig. 1 is an optical microscope image (magnification: 50 times) of a section of a workpiece prepared by using the laser forming method of the present invention and using nano-TiC, TiB ₂ and Al ₂ O ₃ particles to reinforce a nickel-based superalloy.

Fig. 2 is an optical microscope image (magnification: 1000 times) of the cross-section of the workpiece prepared by using the laser forming method of the present invention and using nano-TiC, TiB ₂ and Al ₂ O ₃ particles to reinforce the nickel-based superalloy.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope of the present invention.

A multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy, with the nickel-based superalloy as the matrix, adding TiC, TiB ₂ and Al ₂ O ₃ particle reinforcement phases with a particle size of 40-100 nm, and adding TiC, TiB ₂ and Al The weight percentages of ₂ O ₃ are respectively 2.0-4.0%, 2.0-4.0%, and 1.0-3.0% of the multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy.

Wherein, the nickel-based superalloy as the matrix is a regular spherical gas atomized powder with a particle size of 15-45 μm.

Wherein, according to the percentage by weight, the composition of the nickel-based superalloy as the matrix is: 21-23% Cr, 4-5% Fe, 0.1-0.4% Ti, 0.1-0.4% Al, 4-4.15% Nb, 8-10% Mo, 0.01-0.1% C and the balance Ni.

A laser forming method for multiphase nano-ceramic particle hybrid reinforced nickel-based superalloy, the multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy takes nickel-based superalloy as the matrix, and adds TiC and TiB with a particle size of 40-100nm ₂ and Al ₂ O ₃ are reinforcing phases, and the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ added are respectively 2.0-4.0%, 2.0-4.0%, 1.0 ~3.0%;

The laser shaping method comprises the following steps:

(1) According to the performance requirements of the formed part, the TiC, TiB ₂ and Al ₂ O ₃ particles of the stated ratio are added to the nickel-based superalloy matrix to obtain a mixed powder;

(2) Under argon protection, use a ball mill to perform high-energy ball milling on the mixed powder in step (1) to obtain a uniformly mixed powder;

(3) Establish a three-dimensional CAD model of the part to be formed on the computer; use software to slice and layer the model to obtain a series of two-dimensional planes, and determine the laser scanning route; through the numerical control system, use the focused high-energy laser beam to perform step (2) The uniformly mixed powder in the machine is reciprocally scanned according to the determined scanning route, powder is spread layer by layer, fused and accumulated layer by layer, and superimposed layer by layer until a three-dimensional part is formed.

Wherein, the nickel-based superalloy as the matrix is a regular spherical gas atomized powder with a particle size of 15-45 μm.

Wherein, according to the percentage by weight, the composition of the nickel-based superalloy as the matrix is: 21-23% Cr, 4-5% Fe, 0.1-0.4% Ti, 0.1-0.4% Al, 4-4.15% Nb, 8-10% Mo, 0.01-0.1% C and the balance Ni.

Wherein, in the step (2), the ball-to-material ratio is 5:1-4:1, the ball-milling speed is 150-200 rpm, and the ball-milling time is 4-5 hours. Due to the high speed of the high-energy ball milling method, the output energy is enough to cause large plastic deformation of the powder and the crushing of the reinforcement phase particles. At the same time, the shape of the reinforcement phase particles and The uniformity of particle distribution of the reinforcement phase is improved.

Wherein, what used in the step (3) is a YLR-200 fiber laser with a maximum output power of 200W.

Wherein, in the step (3), the laser process parameters are as follows: the laser spot diameter is 70-100 μm, the laser power is 100-160 W, the laser scanning rate is 300-500 mm/s, and the laser scanning distance is 50-90 μm.

Embodiment 1

The matrix material is a nickel-based superalloy with a particle size of 15-30 μm, which is a regular spherical gas atomized powder, and the reinforcing phase is an irregular polygonal powder of TiC, TiB ₂ and Al ₂ O ₃ with a particle size of 50 nm. The composition of the nickel-based superalloy is: 21% Cr, 5% Fe, 0.4% Ti, 0.4% Al, 4.15% Nb, 8% Mo, 0.1% C and the balance Ni (weight percentage). The weight percentages of the reinforcing phases TiC, TiB ₂ and Al ₂ O ₃ are respectively 3.5%, 3.5% and 2.5% of the total weight of the multiphase nano-ceramic particle hybrid reinforced nickel-based superalloy.

The preparation steps of the heterogeneous nano-ceramic particle hybrid reinforced nickel-based superalloy are as follows:

(1) According to the performance requirements of the formed part, the TiC, TiB ₂ and Al ₂ O ₃ particles of the stated proportion are added to the nickel-based superalloy to obtain a mixed powder;

(2) The mixed powder is subjected to ball milling and mixing treatment: the mixed powder is subjected to high-energy ball milling using a Pulverisette 6 single-pot planetary high-energy ball mill (Fristsch Company, Germany). In the process of ball milling and mixing, in order to prevent the powder from being oxidized, it is necessary to add protective gas argon. The ball-to-material ratio is 5:1, the ball milling speed is 200rpm, and after 4 hours of ball milling, a uniformly mixed powder is finally obtained;

(3) Establish a three-dimensional CAD model of the part to be formed on the computer; use software to slice and layer the model according to a certain thickness, obtain a series of two-dimensional planes, and determine the laser scanning route; Fixed on the platform, the sealing device is filled with argon as a protective gas. The high-energy laser beam is used to repeatedly scan the substrate for preheating, and then through the automatic powder spreading equipment, the mixed powder after ball milling and mixing is evenly spread on the forming cylinder substrate, and the thickness of the powder spreading is 50 μm. Through the CNC forming system, the focused high-energy laser beam is used to reciprocate and scan the uniformly mixed powder laid on the base plate of the forming cylinder according to the prescribed route to make it melt and solidify rapidly. Then repeat the steps of powder spreading→laser scanning, powder spreading layer by layer, fused and accumulated layer by layer, and superimposed layer by layer until a three-dimensional part is formed. Among them, the laser process parameters are as follows: the laser spot diameter is 70 μm, the laser power is 150 W, the laser scanning rate is 400 mm/s, and the laser scanning distance is 55 μm. After forming, cool to room temperature and take out.

Fig. 1 is the optical microstructure diagram of the cross-section of the workpiece obtained by composite preparation of nano-TiC, TiB ₂ and Al ₂ O ₃ particles reinforced nickel-based superalloy by adopting the laser forming method of the present invention (magnification is 50 times). According to Fig. 1, it can be seen that good metallurgical bonding is obtained between the layers of the sample prepared by the present invention, without any obvious defects such as holes and delamination, and the density is relatively high.

Fig. 2 is a microstructure diagram of a cross-section of a workpiece obtained by composite preparation of a nickel-based superalloy compounded with nano-TiC, TiB ₂ and Al ₂ O ₃ particles using the laser forming method of the present invention (magnification is 1000 times). According to the content of Fig. 2, it can be seen that the sample prepared by the present invention obtains a refined columnar dendrite microstructure. Refined dendrites are beneficial for alloy materials to obtain higher mechanical properties, such as hardness, wear resistance, and tensile properties.

Embodiment 2

The difference between this embodiment and Embodiment 1 is that the weight percentages of the reinforcing phases TiC, TiB ₂ and Al ₂ O ₃ are 2.5%, 2.5%, and 1.5% respectively, and the composition of the nickel-based superalloy as the matrix is: 23% Cr , 4% Fe, 0.1% Ti, 0.1% Al, 4% Nb, 10% Mo, 0.01% C and the balance Ni, the others are the same as those of the first embodiment.

Embodiment 3

This embodiment differs from Embodiment 1 in that the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ in the reinforcement phases are 2.0%, 2.0%, and 1.0% respectively, and the particle size of the reinforcement phase is 40nm. Others are the same as Embodiment 1.

Embodiment 4

The difference between this embodiment and Embodiment 1 is that the weight percentages of TiC, TiB ₂ and Al ₂ O ₃ in the reinforcement phases are 4.0%, 4.0%, and 3.0% respectively, and the particle size of the reinforcement phase is 100nm. Others are the same as Embodiment 1.

Embodiment 5

The difference between this embodiment and Embodiment 1 is that the laser power is 100W, and the laser scanning rate is 300mm/s, and the others are the same as Embodiment 1.

Embodiment 6

The difference between this embodiment and Embodiment 1 is that the laser power is 160W, and the laser scanning speed is 500mm/s, and the others are the same as Embodiment 1.

Comparative example 1

In this comparative example, forging (traditional method) is used to prepare nano-TiC, TiB ₂ and Al ₂ O ₃ particle-reinforced nickel-based superalloy composite materials, and the others are the same as Embodiment 1. After the completion, the mechanical properties of the formed parts are tested, and then compared with the composite materials prepared by laser rapid prototyping.

Comparative example 2

In this comparative example, casting (traditional method) is used to prepare nano-TiC, TiB ₂ and Al ₂ O ₃ particle-reinforced nickel-based superalloy composite materials, and the others are the same as Embodiment 1. After the completion, the mechanical properties of the formed parts are tested, and then compared with the composite materials prepared by laser rapid prototyping.

Comparative example 3

The difference between this comparative example and Embodiment 1 is that the particle diameters of the reinforcing phase materials TiC, TiB ₂ and Al ₂ O ₃ are 10-15 μm, and the others are the same as Embodiment 1.

Comparative example 4

The difference between this comparative example and Embodiment 1 is that the reinforcement phase only has TiC powder with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 5

The difference between this comparative example and Embodiment 1 is that the reinforcement phase only has TiB ₂ powder with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 6

The difference between this comparative example and Embodiment 1 is that the reinforcing phase only has Al ₂ O ₃ powder with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 7

The difference between this comparative example and Embodiment 1 is that the reinforcement phase only has TiC and TiB ₂ powders with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 8

The difference between this comparative example and Embodiment 1 is that the reinforcement phase only has TiC and Al ₂ O ₃ powders with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 9

The difference between this comparative example and Embodiment 1 is that the reinforcement phase only has TiB ₂ and Al ₂ O ₃ powders with a particle size of 50 nm, and the others are the same as Embodiment 1.

Comparative example 10

The difference between this comparative example and Embodiment 1 is that the weight percentages of the reinforcing phases TiC, TiB ₂ and Al ₂ O ₃ are 4.5%, 4.5%, and 3.5% respectively, and the others are the same as Embodiment 1.

Comparative example 11

This comparative example is different from Embodiment 1 in that the laser power is 80W, and the others are the same as Embodiment 1.

Comparative example 12

The difference between this comparative example and Embodiment 1 is that the laser power is 200W, and the others are the same as Embodiment 1.

Comparative example 13

This embodiment differs from Embodiment 1 in that the laser scanning rate is 200 mm/s, and the others are the same as Embodiment 1.

Comparative example 14

The difference between this embodiment and Embodiment 1 is that the laser scanning rate is 600 mm/s, and the others are the same as Embodiment 1.

Table 1 shows the different mechanical properties of the nickel-based alloy composite formed parts prepared in various examples and comparative examples. Table 1 shows the comparison of mechanical properties of various prepared and formed nickel-based alloy composites under different forming process parameters, different raw material powder ratios and size conditions. Traditional processing methods (such as forging in Comparative Example 1 and casting in Comparative Example 2) cannot solve the problems of uniform distribution of reinforcing particles and poor interface bonding, resulting in poor mechanical properties of formed parts. The parts prepared by laser forming by the method can obtain excellent hardness, tensile strength and yield strength due to uniform distribution of reinforcing particles and good metallurgical bonding at the interface. In laser forming methods, small differences in laser power and scan rate can also lead to differences in the properties of the final shaped part. Compared with other conditions, the multi-phase nano-ceramic particle hybrid reinforced nickel-based superalloy composite material formed part prepared by the method of the present invention has obvious improvement.

The invention adopts nano TiC, TiB ₂ and Al ₂ O ₃ particles to mix and strengthen the nickel-based superalloy, so that the composite material parts have good hardness, strength, tensile properties, high temperature corrosion resistance, wear resistance, high temperature creep properties And other performance advantages, can meet the special performance requirements of the hot end parts of the aero-engine at high temperature. The method of the present invention can overcome the agglomeration effect brought by the huge surface energy of the nanoparticles, inhibit the agglomeration of the particles, and make the particles evenly distributed; at the same time, the wettability between the reinforcing phase and the metal matrix is improved through high-temperature melting and rapid solidification of laser molding And interface problems, and enable the nanoparticle-reinforced phase to maintain its nanoparticle characteristics, so that the final manufactured parts have excellent metallurgical bonding, high density, fine and compact microstructure, and excellent mechanical properties. In addition, the method of the invention is simple and easy to operate, the process and each parameter are easy to control, and there are few side reactants.

In addition to the above-mentioned embodiments, the present invention can also be implemented in other ways, and any obvious replacements are within the protection scope of the present invention without departing from the content of the present invention.

Claims (9)

1. a kind of multiphase nano-ceramic particle hybrid buildup nickel base superalloy, which is characterized in that the multiphase nano ceramics Grain hybrid buildup nickel base superalloy is using nickel base superalloy as matrix, TiC, TiB that addition grain size is 40~100nm₂With Al₂O₃Particle is reinforced phase, adds TiC, TiB₂And Al₂O₃Weight percent be respectively that the multiphase nano-ceramic particle mixes Enhance 2.0~4.0%, 2.0~4.0%, the 1.0~3.0% of nickel base superalloy.

2. multiphase nano-ceramic particle hybrid buildup nickel base superalloy as described in claim 1, which is characterized in that the work Nickel base superalloy for matrix is the gas atomized powder for the regular spherical that grain size is 15~45 μm.

3. multiphase nano-ceramic particle hybrid buildup nickel base superalloy as described in claim 1, which is characterized in that according to weight Percentage is measured, the group of the nickel base superalloy as matrix is divided into：21~23%Cr, 4~5%Fe, 0.1~0.4%Ti, 0.1~0.4%Al, 4~4.15%Nb, 8~10%Mo, 0.01~0.1%C and surplus Ni.

4. a kind of laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy, which is characterized in that described For multiphase nano-ceramic particle hybrid buildup nickel base superalloy using nickel base superalloy as matrix, addition grain size is 40~100nm TiC, TiB₂And Al₂O₃For reinforced phase, TiC, TiB are added₂And Al₂O₃Weight percent be respectively the multiphase nano ceramics Confusion enhances 2.0~4.0%, 2.0~4.0%, the 1.0~3.0% of nickel base superalloy；

The laser formation method includes the following steps：

(1) TiC, TiB of the ratio are added in nickel base superalloy matrix₂And Al₂O₃Particle obtains mixed-powder；

(2) under protection of argon gas, high-energy ball milling is carried out to the mixed-powder in step (1) using ball mill, obtains uniformly mixing Powder；

(3) three-dimensional CAD model of wanted formation of parts is established on computers；Model slice is layered using software, obtains one Serial two dimensional surface determines laser scanning route；By digital control system, using the high energy laser beam of focusing in step (2) Uniform mixed-powder is by determining scanning route shuttle-scanning, and successively powdering, successively consolidation accumulation is layering, until being formed 3 d part.

5. the laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy as claimed in claim 4, It is characterized in that, the nickel base superalloy as matrix is the gas atomized powder for the regular spherical that grain size is 15~45 μm.

6. the laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy as claimed in claim 4, It is characterized in that, according to weight percent, the group of the nickel base superalloy as matrix is divided into：21~23%Cr, 4~5% Fe, 0.1~0.4%Ti, 0.1~0.4%Al, 4~4.15%Nb, 8~10%Mo, 0.01~0.1%C and surplus Ni.

7. the laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy as claimed in claim 4, Be characterized in that, in the step (2), ratio of grinding media to material 5: 1~4: 1, rotational speed of ball-mill be 150~200rpm, Ball-milling Time be 4~ 5h。

8. the laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy as claimed in claim 4, It is characterized in that, used in step (3) is the YLR-200 optical fiber lasers that peak power output is 200W.

9. the laser forming method of multiphase nano-ceramic particle hybrid buildup nickel base superalloy as claimed in claim 4, It is characterized in that, in the step (3), laser technical parameters are as follows：70~100 μm of laser spot diameter, laser power 100~ 160W, 300~500mm/s of laser scan rate, 50~90 μm of laser scanning spacing.