CN111778503A - Crucible-free laser micro-area metallurgy method and application based on laser light-receiving path control - Google Patents

Abstract

The invention discloses a crucibleless laser micro-area metallurgy method based on laser light-receiving path regulation. The method includes: first, preparing raw material powder; second, designing multiple laser micro-area metallurgy schemes; and third, establishing laser micro-area metallurgical parameters The relationship with the micro-area material; 4. Design the corresponding laser micro-area metallurgical parameters according to the structure and performance requirements of the target product; 5. Prepare the micro-area material; Application of a regulated crucible-free laser micro-metallurgy method for rapid verification in computational materials science. The invention utilizes the laser to make the powder around the micro-area molten pool self-generate "metallurgical crucible", realizes short-period micro-area metallurgy without matrix and crucible, and adjusts the laser waveform according to the characteristics of the raw material powder to determine the laser light-receiving path, and realizes the micro-area metallurgy The controllability of the cooling and solidification stage can control the phase structure of the micro-area material; the application of the invention provides an efficient and fast verification method for computational materials science.

Description

Crucible-free laser micro-area metallurgy method and application based on laser light-receiving path control

technical field

The invention belongs to the technical field of metallurgy, and in particular relates to a crucibleless laser micro-area metallurgical method and application based on laser light receiving path regulation.

Background technique

From the original Stone Age to the modern era of new materials, material innovation has always been the technological key to subverting the development of the times. For the world, countries that prioritize the development of new materials will be at the forefront of the industrial revolution in the 21st century. Therefore, how to develop innovative materials with high efficiency in a short period of time and accelerate the process of research and development of new materials has become the direction of efforts of various countries. However, in the process of accelerating the research and development of new materials, the following bottleneck problems need to be solved:

(1) The research and development of existing materials to new materials relies on existing scientific experience and trial and error in more cases. The whole process has a long cycle and low efficiency, especially when the traditional smelting method is used for testing, which reflects the long cycle. , the research process is cumbersome, the investment cost is high, and the efficiency is extremely low;

(2) The difficulty of testing and alloy melting has promoted the development of computational materials science. The method of computational materials science can quickly calculate the structure and properties of different new materials, and at the same time calculate the influence of solidification parameters on the material structure and properties, and establish the material structure. , performance and solidification parameters. However, how to verify the materials quickly designed by computational materials science and their correlation with solidification conditions has become a bottleneck that needs to be broken through. Especially in the field of refractory alloys, due to the high melting point of refractory alloys, on the one hand, there is a lack of suitable materials as melting crucibles. Alloy materials are fused, so that the calculation results cannot be verified, and the in-depth development of the field of computational materials science is greatly hindered, which restricts the development of new materials.

Based on the above analysis, it is urgent to propose a new technology that can realize the rapid preparation of materials and solve the melting problems of high melting point refractory materials (such as: crucible selection problem, molten pool convection problem, metallurgical uniformity problem). At the same time, it satisfies the rapid metallurgical technology of materials with continuously adjustable solidification conditions, and the technical method that efficiently, green and accurately meets the verification requirements of computational materials science.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a crucible-free laser micro-area metallurgical method based on the regulation of the laser light-receiving path, aiming at the deficiencies of the above-mentioned prior art. The method utilizes the high energy of the laser to make the powder around the micro-area molten pool self-generate a "metallurgical crucible", so that the micro-area molten pool realizes short-period micro-area metallurgy without matrix and crucible, and establishes the laser micro-area metallurgical parameters and micro-area metallurgy. The relationship between material structure and properties, so as to adjust the laser waveform according to the characteristics of the raw material powder to determine the laser light-receiving path, which can improve the controllability of the metallurgical cooling and solidification stage of the entire micro-area and help the phase structure transformation of the alloy, so as to obtain the structure distribution. Homogeneous microdomain material.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is: a crucible-free laser micro-area metallurgical method based on laser light-receiving path regulation, is characterized in that, the method comprises the following steps:

Step 1: According to the requirements of the powder particle size range of the powder bed of the laser micro-area metallurgical equipment, use the element mixing method to carry out powder mixing according to the design components of the target product, and then dry to obtain the raw material powder;

In step 2, the laser micro-area metallurgical parameters are combined and designed according to the characteristics of the raw material powder obtained in step 1, and a plurality of different laser micro-area metallurgy schemes including laser power, laser action time and laser light-receiving path are obtained; the The laser action time and the laser light receiving path are controlled by the laser waveform;

Step 3: Using the raw material powder obtained in step 1, carry out crucible-free laser micro-metallurgy respectively according to the multiple laser micro-area metallurgy schemes obtained in step 2, and use the method of laser melting pool fixed-point temperature measurement to measure each crucible-free laser micro-area. The molten pool temperature and the solidification parameters including the solidification temperature and temperature gradient in the metallurgical process were measured, and the influence of laser power and laser action time on the degree of convection in the molten pool, as well as the influence of the laser light receiving path on the solidification conditions of the molten pool, were obtained. Micro-area materials with different structures and properties, and then establish the relationship between laser micro-area metallurgical parameters and micro-area materials;

Step 4: Design the corresponding laser micro-metallurgical parameters according to the relationship between the laser micro-area metallurgical parameters and the micro-area materials established in step 3, as well as the organization and performance requirements of the target product;

Step 5. According to the laser micro-area metallurgy parameters designed in step 4, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 501, laying the raw material powder on the horizontal carrier; the thickness of the laying is 2mm-20mm;

Step 502: Set the laser power and laser action time, and at the same time adjust the laser waveform to set the solidification parameters, and then use the laser to perform laser micro-area fixed-point melting on the raw material powder laid on the horizontal carrier in step 501, so that the raw material powder is melted and pressed. The set solidification parameters are solidified to obtain micro-domain materials.

The requirements of the powder particle size range for powder laying of the laser micro-area metallurgical equipment used in the present invention are: the powder should have a reasonable particle size range. When the particle size of the powder is too small, the powders will absorb each other and agglomerate. The smaller the particle size of the powder, the larger the specific surface area of the powder and the higher the specific surface energy, which will lead to the poor powder spreading effect of the powder, and the phenomenon of overheating is easy to occur during the laser action process. , causing droplet splashing and affecting the quality of micro-area materials; when the particle size of the powder is large, during the laser action process, the effective energy of the laser cannot meet the demand for melting the powder particles, and the melting between the powders is incomplete, which seriously affects the micro-particles. Density and mechanical properties of regional materials.

According to the requirements of the powder particle size range for powder laying of laser micro-area metallurgy equipment, the present invention mixes and dries each component powder of the target product as the raw material powder, and then adopts the laser micro-area metallurgy method to prepare the micro-area material. During the process, only the raw material powder in the range of the laser spot micro-area is heated and melted to form a molten pool, and the raw material powder around the micro-area is still in a solid state and has not been melted, so that the raw material powder around the micro-area self-generates a "metallurgical crucible" , Utilizing the characteristics of a large amount of heat dissipation of the raw material powder around the micro-area, the micro-area molten pool realizes short-period micro-area metallurgy without a matrix and no crucible; at the same time, due to the use of a high-energy laser beam as the input heat source for the raw material powder melting, the entire molten pool is melted. Strong convection is achieved in the body, and the molten pool temperature that can fully melt the powder material is obtained. Combined with the set process parameters, the melting time is precisely controlled by the laser action time, and a more uniform and sufficient metallurgical effect is achieved, especially for refractory alloy materials. , a refractory alloy with uniform composition can be obtained. Therefore, different from directly selecting the laser waveform for heating and smelting in the prior art, the present invention firstly adjusts the metallurgical parameters of the laser micro-area including laser power, laser action time, laser light receiving path (laser action time and laser light receiving path) according to the characteristics of the raw material powder. The optical path is controlled by the laser waveform, and the laser waveform determines the laser light receiving path, that is, determines the solidification conditions of the raw material powder after smelting). In metallurgy, the method of laser molten pool fixed-point temperature measurement is used to measure and investigate the influence of laser power and laser action time on the degree of convection in the molten pool, as well as the influence of the laser light receiving path on the solidification conditions of the molten pool, and obtain micro-regions with different structures and properties. materials, and then establish the relationship between the laser micro-area metallurgical parameters and the micro-area materials, and based on this, according to the structure and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters, and carry out crucible-free laser micro-area metallurgy, The microdomain material is prepared. The method of the invention designs the laser waveform in advance according to the characteristics of the raw material powder, so that the laser beam repeatedly acts on the molten pool formed by powder melting, which improves the controllability of the whole micro-area metallurgical heating, melting, cooling and solidification stages, and at the same time helps the refractory melting The phase structure of the alloy is transformed, and the metallurgical action time can be flexibly controlled by adjusting the metallurgical parameters of the laser micro-area with a high degree of maneuverability, and the size of the molten pool can be controlled from micrometers to millimeters. Micro-area materials; at the same time, because the limitation of metallurgical conditions on crucible and matrix material selection is lifted, it provides a zero-pollution environment for the entire laser micro-area metallurgical process.

The above-mentioned crucibleless laser micro-area metallurgy method based on laser light-receiving path regulation is characterized in that the mass purity of each component powder of the target product described in step 1 is more than 99%, and the particle size range is 3 μm～150 μm.

The above-mentioned crucible-free laser micro-area metallurgy method based on laser light-receiving path regulation is characterized in that the element mixing method described in step 1 is a direct mixing method, or a method combining mechanical mixing and ball milling, or an adhesive coating method . The direct mixing method is to directly mechanically mix the powder of each element of the material according to the designed distribution ratio; the method of combining mechanical mixing and ball milling is to mechanically mix each component powder according to the designed distribution ratio, and then use a ball mill for ball milling treatment; The bonding coating method is to divide the powder of each component of the material according to the designed distribution ratio and add PVA (polyvinyl alcohol) glue as the powder binder, and then perform ball milling until the mixture is uniform. The element mixing method of the present invention is diverse and applicable to a variety of materials.

The above-mentioned crucibleless laser micro-area metallurgy method based on laser light-receiving path regulation is characterized in that, the equipment used in the drying treatment in step 1 is a vacuum drying furnace, and the temperature of the drying treatment is 70 ℃ ~ 125 ℃, and the time It is 2h～8h, and the vacuum degree is -0.05MPa～-0.085MPa. The preferred drying treatment equipment and process parameters can effectively remove the moisture adsorbed in each component powder of the target product after proportioning and mixing, reduce the influence on the subsequent laser micro-area metallurgical process, and improve the metallurgical quality of the micro-area material.

对应的0<θ≤30°，或者

对应的30°<θ≤60°，或者

对应的60°<θ<90°。其中

对应的0<θ≤30°实现了熔池的慢 速凝固(如图1a所示)，有利于微区材料形成平衡相组成的组织，

对应的30°<θ≤60°，实现了熔池的中速凝固(如图1b所 示)，微区材料形成平衡相和非平衡相组成的混合组织，

对应的 60°<θ<90°实现了熔池的快速凝固(如图1c所示)，有利于微区材料形 成非平衡相组成的组织，从而有利于根据目标产物的凝固特性选择对应的 激光波形，通过调节不同凝固参数，得到具有不同组织与性能的微区合金 材料，适应了不同特性铺设粉末的要求，提高了本发明方法的适用范围。The above-mentioned crucibleless laser micro-area metallurgy method based on laser light-receiving path regulation is characterized in that the laser power in step 502 is 100W-10000W, the laser action time is 5ms-50s, and the laser waveform is a rectangular waveform or a right-angled trapezoidal waveform , the right-angle trapezoidal waveform includes the peak power continuous stage and the power decay stage of the laser, and the right-angle trapezoidal waveform in the power decay stage is adjusted with the slope k of the hypotenuse and the angle θ of the hypotenuse, where k=tanθ, and the value range of the slope k is

The corresponding 0<θ≤30°, or

The corresponding 30°<θ≤60°, or

The corresponding 60°<θ<90°. in

The corresponding 0<θ≤30° realizes the slow solidification of the molten pool (as shown in Fig. 1a), which is conducive to the formation of the equilibrium phase composition of the micro-domain material.

Corresponding to 30°<θ≤60°, the medium-speed solidification of the molten pool is realized (as shown in Figure 1b), and the micro-domain material forms a mixed structure composed of equilibrium phase and non-equilibrium phase.

The corresponding 60°<θ<90° realizes the rapid solidification of the molten pool (as shown in Figure 1c), which is conducive to the formation of a non-equilibrium phase structure of the micro-domain material, which is conducive to the selection of the corresponding laser according to the solidification characteristics of the target product Waveform, by adjusting different solidification parameters, micro-area alloy materials with different structures and properties can be obtained, which can meet the requirements of laying powder with different characteristics and improve the application range of the method of the present invention.

Theoretically speaking, increasing the laser power P and increasing the laser action time T can make the molten pool get sufficient heat input, and realize strong convection in the molten pool. If it is too long, the laser action time T is too long, which will lead to overheating of the molten pool and splashing of molten droplets, which will affect the surface quality of the micro-area material and the quality of the internal structure. Therefore, the preferred process parameters take into account sufficient heat input and suitable convection in the molten pool, so that the prepared micro-domain material has both excellent microstructure and mechanical properties.

In addition, the present invention also provides an application of a crucible-free laser micro-area metallurgical method based on laser light-receiving path regulation in the rapid verification of computational materials science, characterized in that the specific process of the application is: first, according to computational materials science The solidification conditions of the research object material design, the laser light receiving path is set by adjusting the laser waveform in the laser micro-area metallurgical equipment to ensure consistent solidification conditions, and the laser micro-area metallurgical parameters are obtained. Then, the microstructure and performance parameters of the micro-area material were measured, and the simulation results of computational materials were compared and verified to determine the accuracy of the simulation results of the microstructure and performance parameters of the research object materials. For the deviation from the test results, the calculation parameters are modified, and the metallurgical parameters of the laser micro-area are adjusted by feedback. match.

At present, in the field of computational materials science, the computationally obtained refractory/extremely refractory materials are difficult to verify in practical experiments and the verification efficiency is low. Since the preparation method of the crucibleless laser micro-area material of the present invention realizes the rapid preparation of the micro-area material, the corresponding micro-area material is quickly prepared by the method of the present invention according to the material structure and performance designed by computational material science, Then perform performance verification: for example, the calculated elastic modulus and microhardness are quickly verified by micro- and nano-indentation test methods; the width of grains is quickly verified by Image pro software; the grain growth mode is quickly verified by electron backscatter diffraction. This application satisfies the rapid verification requirements of computational materials science, and provides an efficient and accurate verification technology for the field of computational materials science.

Compared with the prior art, the present invention has the following advantages:

1. The present invention detects the metallurgical parameters of the laser micro-area by using the method of fixed-point temperature measurement of the laser molten pool, and establishes the relationship between the metallurgical parameters of the laser micro-area and the micro-area material structure and performance, so as to adjust the laser waveform according to the characteristics of the raw material powder. The laser light-receiving path can improve the controllability of the metallurgical cooling and solidification stage of the whole micro-area, and at the same time help the phase structure transformation of the refractory alloy, so as to obtain a micro-area material with uniform structure distribution.

2. The present invention adopts the laser micro-area metallurgy method to prepare micro-area materials, and utilizes the high energy of the laser to fully melt the characteristics of metal powder, so that the powder around the micro-area molten pool can self-generate a "metallurgical crucible", and the powder around the micro-area can be used for a large number of The characteristics of heat dissipation enable the micro-area molten pool to realize short-period micro-area metallurgy without matrix and crucible, and at the same time relieve the limitation of metallurgical conditions on the selection of crucible and matrix material, and provide a zero-pollution environment for the laser micro-area metallurgy process.

3. The present invention uses a high-energy laser beam as the input heat source for raw material powder smelting, so that strong convection is realized in the entire molten pool melt. Combined with the set process parameters, the smelting time is precisely controlled by the laser pulse width, and a more uniform and sufficient metallurgy is realized. In addition, the micro-area metallurgy is performed according to the raw material powder and the laser waveform designed for the raw material powder, which not only improves the controllability of the whole micro-area metallurgical cooling and solidification stage, but also helps the phase structure transformation of the micro-area material, and realizes metallurgy-materials. Integrated preparation.

4. The surface of the micro-area material prepared by the present invention is uniform and smooth, without pores and oxidation, the product material is uniform, the metallurgical quality is good, the product crystal grain and the composition distribution are uniform, and the metallurgy of the high-hardness and high-melting-point material can be realized.

5. The preparation method of the present invention is simple, efficient and energy-saving, green and environmentally friendly, suitable for the field of high-throughput micro-area material preparation, and has broad application prospects in the field of material genetic engineering.

6. The preparation method of the present invention has the advantages of simple process and fast response, and is applied to the field of computational materials science, overcoming the shortcomings of difficulty and low efficiency in verification of the research object material in actual experiments, and has a wide application range and is efficient and accurate in verification.

7. The preparation method of the present invention not only realizes the rapid micro-area preparation of new materials, obtains new materials efficiently and immediately, shortens the preparation period, but also obtains the correlation between the microstructure and properties of the alloy material and the solidification rate, so that the different solidification rates can be achieved. Acquisition of microdomain materials with continuously tunable tissue and properties.

8. The application of the present invention provides an efficient and fast verification method for computational materials science, and the verification efficiency is significantly improved compared with the traditional smelting method.

The technical solutions of the present invention will be further described in detail below through the accompanying drawings and embodiments.

Description of drawings

Fig. 1a is a schematic diagram of the slow solidification right-angle trapezoidal waveform adopted in the present invention.

Fig. 1b is a schematic diagram of a medium-speed solidification right-angled trapezoidal waveform adopted in the present invention.

Fig. 1c is a schematic diagram of the rapid solidification right-angle trapezoidal waveform adopted in the present invention.

2 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in Example 1 of the present invention.

3 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in Example 2 of the present invention.

4 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in Example 3 of the present invention.

5 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in Example 4 of the present invention.

6 is an EDS scanning diagram of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Figure 7a is a diagram showing the total distribution of the content of each element in the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Figure 7b is an EDS composition distribution diagram of the Ti element content of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Figure 7c is an EDS composition distribution diagram of Al element content of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Figure 7d is an EDS composition distribution diagram of Mo element content of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Fig. 8a is an EDS line scanning macroscopic topography diagram of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

Figure 8b is a data diagram of the content of each element by EDS line scanning of the Ti-6Al-3Mo microdomain material prepared in Example 5 of the present invention.

9 is a microstructure diagram of the Ti-6Al-3Mo microdomain material prepared in Example 6 of the present invention.

FIG. 10 is a process flow diagram of Embodiment 7 of the present invention.

Figure 11a is a microstructure diagram of the Ti-6Al-4V-0.3B microdomain material 1 prepared in Example 7 of the present invention.

Figure 11b is a microstructure diagram of the Ti-6Al-4V-0.3B microdomain material 2 prepared in Example 7 of the present invention.

Figure 12 is a microstructure diagram of the Ti-6Al-4V-0.5B microdomain material prepared in Example 8 of the present invention.

Detailed ways

The crucible-free laser micro-region metallurgy method based on the regulation of laser light-receiving path of the present invention is described in detail through Examples 1 to 6.

Example 1

This embodiment includes the following steps:

Step 1. Combine industrial pure Ti powder with a mass purity of 99% and an average particle size of 130 μm, industrial pure Al powder with a mass purity of 99% and an average particle size of 10 μm, and industrial pure Al powder with a mass purity of 99% and a particle size of 30 μm The pure V powder was directly mixed according to the designed distribution ratio of Ti-6Al-4V, and then placed in a vacuum drying furnace, and dried for 2 hours at a temperature of 125°C and a vacuum degree of -0.085MPa to obtain raw material powder;

对应的0<θ≤30°，或者

对应的30°<θ≤60°，或者

对应的60°<θ<90°； 所述激光作用时间和激光收光路径均通过激光波形进行控制；In step 2, the laser micro-area metallurgical parameters are combined and designed according to the characteristics of the raw material powder obtained in step 1, and a plurality of different laser micro-area metallurgy schemes including laser light receiving paths of laser power and laser action time are obtained, wherein, Laser power P can be segmented according to actual metallurgical conditions: low power range 100W≤P<2000W, medium power range 2000W≤P<6000W, high power range 6000W≤P≤10000W; laser action time T is segmented as: short time range 3ms≤T<30ms, medium time range 3ms≤T<3s, long time range 3s≤T≤50s; the laser waveform is a rectangular waveform or a right-angled trapezoidal waveform, and the right-angled trapezoidal waveform includes the peak power continuous phase and the power decay phase of the laser , and the right-angle trapezoidal waveform in the power decay stage is adjusted with the slope k of the hypotenuse and the angle θ of the hypotenuse, where k=tanθ, and the value range of the slope k is

The corresponding 0<θ≤30°, or

The corresponding 30°<θ≤60°, or

The corresponding 60°<θ<90°; the laser action time and the laser light receiving path are controlled by the laser waveform;

Step 3: Using the raw material powder obtained in step 1, carry out crucible-free laser micro-metallurgy respectively according to the multiple laser micro-area metallurgy schemes obtained in step 2, and use the method of laser melting pool fixed-point temperature measurement to measure each crucible-free laser micro-area. The molten pool temperature and the solidification parameters including the solidification rate and temperature gradient in the metallurgical process were measured. Micro-area materials with different structures and properties, and then establish the relationship between laser micro-area metallurgical parameters and micro-area materials, as follows: (1) In the low power range, it is easy to produce more metallurgical defects, such as cracks, pores, etc. problems, especially refractory alloy micro-area materials; in the medium power range, most of the micro-area materials have sufficient heat input to achieve strong convection in the molten pool, and can obtain better metallurgical quality according to the reasonable combination of the combination. Micro-area materials with good formability; in the high power range, due to the large increase in the input heat source, especially for refractory/extremely refractory alloys, better metallurgical effects can be obtained; but for most materials, too high power will The formability of the micro-area material is worse than that in the medium power range; (2) if the micro-area metallurgy is carried out in a short time range, there are metallurgical fusion defects for some materials; if the micro-area metallurgy is carried out in the medium time range, it can be used for most materials. According to the reasonable combination of the combination, micro-area materials with better metallurgical quality and formability are obtained; in the long-term metallurgy, the metallurgical effect of the material is significantly improved, but it has a negative effect on the materials that are easy to crack; (3) Laser light-receiving path In the combination, the slow waveform range realizes the slow solidification of the molten pool, which is conducive to the formation of the equilibrium phase composition of the micro-domain material; the medium-speed waveform range realizes the medium-speed solidification of the molten pool, and the micro-domain material forms the equilibrium phase and non-equilibrium phase. The mixed structure of the phase composition; the rapid waveform range realizes the rapid solidification of the molten pool, which is conducive to the formation of non-equilibrium phase composition of the micro-area material; based on the relationship between the above laser micro-area metallurgical parameters and the micro-area material, according to the target product. The corresponding laser waveform is selected for the solidification characteristics. By adjusting different solidification conditions and combining different metallurgical parameters, micro-domain materials with different structures and properties can be obtained;

Step 4. According to the relationship between the laser micro-area metallurgical parameters and the micro-area materials established in step 3, and according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 5. According to the laser micro-area metallurgy parameters designed in step 4, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 501: Lay the raw material powder on the horizontal titanium plate, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the oxygen in the laser working vacuum box. The content does not exceed 100ppm; the thickness of the laying is 20mm;

对应的θ＝30°，并根据设计的工 艺参数设置激光功率P＝2300W，激光作用时间T＝50s，激光光斑直径 D＝2.2mm，采用激光对步骤501中铺设在水平钛板上的原料粉末进行激光 微区定点熔炼，使得原料粉末熔化后按设定的凝固速率进行凝固，得到 Ti-6Al-4V微区材料；所述Ti-6Al-4V微区材料的半径r＝0.8cm。Step 502: Adjust the laser waveform to be a right-angled trapezoidal waveform and the slope of the right-angled trapezoidal waveform in the power decay stage according to the designed laser waveform

The corresponding θ=30°, and set the laser power P=2300W, the laser action time T=50s, and the laser spot diameter D=2.2mm according to the designed process parameters. Laser micro-area fixed-point smelting is performed, so that the raw material powder is melted and solidified at a set solidification rate to obtain a Ti-6Al-4V micro-area material; the Ti-6Al-4V micro-area material has a radius r=0.8cm.

Fig. 2 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in this embodiment. It can be seen from Fig. 2 that the Ti-6Al-4V microdomain material prepared in this embodiment is a uniformly distributed elongated slab alpha phase and residual beta phase.

中除了

对应的θ还可为0<θ≤30°中除了 θ＝30°之外的其他数值。The slope k of the right-angle trapezoidal waveform in the power decay stage in step 502 of this embodiment can also be a slow waveform range

except

The corresponding θ can also be other values except θ=30° in 0<θ≤30°.

Example 2

This embodiment includes the following steps:

Step 1. Combine industrial pure Ti powder with mass purity of 99% and particle size of 130 μm, industrial pure Al powder with mass purity of 99% and particle size of 10 μm, and industrial pure V with mass purity of 99% and particle size of 30 μm The powder is directly mixed according to the designed distribution ratio of Ti-6Al-4V, then placed in a vacuum drying furnace, and dried for 2 hours under the conditions of a temperature of 125 ° C and a vacuum degree of -0.085 MPa to obtain raw material powder;

Step 2, according to the relationship between the laser micro-area metallurgical parameters and the micro-area material established in the step 3 of Example 1, according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 3. According to the laser micro-area metallurgy parameters designed in step 2, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 301: Lay the raw material powder on the horizontal titanium plate, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the oxygen in the laser working vacuum box. The content does not exceed 100ppm; the thickness of the laying is 20mm;

Step 302: Adjust the laser waveform to be a right-angled trapezoidal waveform according to the designed laser waveform and the slope of the right-angled trapezoidal waveform in the power decay stage k=1, corresponding to θ=45°, and set the laser power P=2300W according to the designed process parameters, the laser The action time is T=25s, and the diameter of the laser spot is D=2.2mm. The raw material powder laid on the horizontal titanium plate in step 301 is subjected to laser micro-area fixed-point melting by laser, so that the raw material powder is melted and solidified according to the set solidification rate. The Ti-6Al-4V microdomain material is obtained; the radius of the Ti-6Al-4V microdomain material is r=0.6 cm.

FIG. 3 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in this embodiment. It can be seen from FIG. 3 that the Ti-6Al-4V microdomain material prepared in this embodiment is uniformly distributed and coexisting. Lath alpha phase, martensite alpha' phase and matrix beta phase.

中除了k＝1、对应的θ还可为30°<θ≤60°中 除了θ＝45°之外的其他数值。The slope k of the right-angled trapezoidal waveform in the power attenuation stage in step 502 of this embodiment may also be in the range of the medium-speed waveform

In addition to k=1, the corresponding θ can also be other values except θ=45° in 30°<θ≤60°.

Example 3

This embodiment includes the following steps:

Step 1. Combine industrial pure Ti powder with a mass purity of 99% and an average particle size of 130 μm, industrial pure Al powder with a mass purity of 99% and an average particle size of 10 μm, and a mass purity of 99% and an average particle size of 30 μm. The industrial pure V powder is directly mixed according to the design distribution ratio of Ti-6Al-4V, and then placed in a vacuum drying furnace, and dried for 8 hours under the conditions of a temperature of 120 ° C and a vacuum degree of -0.07 MPa to obtain raw material powder;

Step 2, according to the relationship between the laser micro-area metallurgical parameters and the micro-area material established in the step 3 of Example 1, according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 3. According to the laser micro-area metallurgy parameters designed in step 2, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 301: Lay the raw material powder on the horizontal titanium plate, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the oxygen in the laser working vacuum box. The content does not exceed 100ppm; the thickness of the laying is 20mm;

Step 302 , according to the designed laser waveform, adjust the laser waveform to be a right-angled trapezoidal waveform and the slope of the right-angled trapezoidal waveform in the power decay stage k=2, corresponding to θ=63.4°, and set the laser power P=2300W according to the designed process parameters, the laser The action time is T=25s, and the diameter of the laser spot is D=2.2mm. The raw material powder laid on the horizontal titanium plate in step 301 is subjected to laser micro-area fixed-point melting by laser, so that the raw material powder is melted and solidified according to the set solidification rate. The Ti-6Al-4V microdomain material is obtained; the radius of the Ti-6Al-4V microdomain material is r=0.4 cm.

FIG. 4 is a microstructure diagram of the Ti-6Al-4V microdomain material prepared in this example. It can be seen from FIG. 4 that the Ti-6Al-4V microdomain material prepared in this example is a uniformly distributed needle-like Martensitic material. bulk α' and residual β phase.

中除了k＝2、对应的θ还可为60°<θ<90°中除了 θ＝63.4°之外的其他数值。The slope k of the right-angle trapezoidal waveform in the power decay stage in step 502 of this embodiment can also be a fast waveform range

In addition to k=2, the corresponding θ can also be other values except θ=63.4° in 60°<θ<90°.

Comparing Fig. 2, Fig. 3 and Fig. 4, it can be seen that by adjusting the laser waveform in the laser micro-metallurgical preparation process, the controllability of the cooling and solidification stage of the whole micro-area metallurgy is improved, and the solidification of laser melting can be expanded. Parameter range, the organization of the micro-area material is regulated, so that the micro-area material with different properties can be obtained, and the application range of the micro-area material is expanded.

Example 4

The difference between this embodiment and Embodiment 3 is that the laser waveform is adjusted to a rectangular waveform, that is, θ=90°.

Fig. 5 is a microstructure diagram of the Ti-6Al-4V micro-domain material prepared in this embodiment. It can be seen from Fig. 5 that the Ti-6Al-4V micro-domain material prepared in this embodiment has a uniform structure and high density. The solidification conditions of this example are basically close to those of the rapid solidification waveform in Example 3, and the obtained structure is the same, but since the laser waveform used in this example is a rectangular waveform, the solidification speed is extremely fast, and a finer acicular martensite is obviously obtained. The organization and the overall metallurgical effect of the material are good.

Example 5

This embodiment includes the following steps:

Step 1. Combine industrial pure Ti powder with mass purity of 99.5% and particle size of 150 μm, industrial pure Al powder with mass purity of 99% and particle size of 15 μm, and industrial pure Mo with mass purity of 99.5% and particle size of 3 μm The powder is mixed mechanically according to the design distribution ratio of Ti-6Al-3Mo, mixed in a planetary ball mill for about 30 minutes, then placed in a vacuum drying furnace, and dried at a temperature of 70°C and a vacuum of -0.05MPa. 3h, to obtain raw material powder;

对应的0<θ≤30°，或者

对应的30°<θ≤60°，或者

对应的60°<θ<90°； 所述激光作用时间和激光收光路径均通过激光波形进行控制；In step 2, the laser micro-area metallurgical parameters are combined and designed according to the characteristics of the raw material powder obtained in step 1, and a plurality of different laser micro-area metallurgy schemes including laser power, laser action time and laser light-receiving path are obtained, wherein, Laser power P can be segmented according to actual metallurgical conditions: low power range 100W≤P<2000W, medium power range 2000W≤P<6000W, high power range 6000W≤P≤10000W; laser action time T is segmented as: short time range 3ms≤T<30ms, medium time range 3ms≤T<3s, long time range 3s≤T≤50s; the laser waveform is a rectangular waveform or a right-angled trapezoidal waveform, and the right-angled trapezoidal waveform includes the peak power continuous phase and the power decay phase of the laser , and the right-angle trapezoidal waveform in the power decay stage is adjusted with the slope k of the hypotenuse and the angle θ of the hypotenuse, where k=tanθ, and the value range of the slope k is

The corresponding 0<θ≤30°, or

The corresponding 30°<θ≤60°, or

The corresponding 60°<θ<90°; the laser action time and the laser light receiving path are controlled by the laser waveform;

Step 3: Using the raw material powder obtained in step 1, carry out crucible-free laser micro-metallurgy respectively according to the multiple laser micro-area metallurgy schemes obtained in step 2, and use the method of laser melting pool fixed-point temperature measurement to measure each crucible-free laser micro-area. The molten pool temperature and the solidification parameters including the solidification rate and temperature gradient in the metallurgical process were measured. Micro-area materials with different structures and properties, and then establish the relationship between laser micro-area metallurgical parameters and micro-area materials, as follows: (1) In the low power range, it is easy to produce more metallurgical defects, such as cracks, pores, etc. problems, especially refractory alloy micro-area materials; in the medium power range, most of the micro-area materials have sufficient heat input to achieve strong convection in the molten pool, and can obtain better metallurgical quality according to the reasonable combination of the combination. Micro-area materials with good formability; in the high power range, due to the large increase in the input heat source, especially for refractory/extremely refractory alloys, better metallurgical effects can be obtained; but for most materials, too high power will The formability of the micro-area material is worse than that in the medium power range; (2) if the micro-area metallurgy is carried out in a short time range, there are metallurgical fusion defects for some materials; if the micro-area metallurgy is carried out in the medium time range, it can be used for most materials. According to the reasonable combination of the combination, micro-area materials with better metallurgical quality and formability are obtained; in the long-term metallurgy, the metallurgical effect of the material is significantly improved, but it has a negative effect on the materials that are easy to crack; (3) Laser light-receiving path In the combination, the slow waveform range realizes the slow solidification of the molten pool, which is conducive to the formation of the equilibrium phase composition of the micro-domain material; the medium-speed waveform range realizes the medium-speed solidification of the molten pool, and the micro-domain material forms the equilibrium phase and non-equilibrium phase. The mixed structure of the phase composition; the rapid waveform range realizes the rapid solidification of the molten pool, which is conducive to the formation of non-equilibrium phase composition of the micro-area material; based on the relationship between the above laser micro-area metallurgical parameters and the micro-area material, according to the target product. The corresponding laser waveform is selected for the solidification characteristics. By adjusting different solidification conditions and combining different metallurgical parameters, micro-domain materials with different structures and properties can be obtained;

Step 4. According to the relationship between the laser micro-area metallurgical parameters and the micro-area materials established in step 3, and according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 5. According to the laser micro-area metallurgy parameters designed in step 4, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 501: Lay the raw material powder on the horizontal titanium plate, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the oxygen in the laser working vacuum box. The content does not exceed 100ppm; the thickness of the laying is 20mm;

对应的θ＝26.6°，并根据设计的工 艺参数设置激光功率P＝2300W，激光作用时间T＝50s，激光光斑直径 D＝2.2mm，采用激光对步骤501中铺设在水平钛板上的原料粉末进行激光 微区定点熔炼，使得原料粉末熔化后按设定的凝固速率进行凝固，得到 Ti-6Al-3Mo微区材料；所述Ti-6Al-4V微区材料的半径r＝0.8mm。Step 502: Adjust the laser waveform to be a right-angled trapezoidal waveform and the slope of the right-angled trapezoidal waveform in the power decay stage according to the designed laser waveform

The corresponding θ=26.6°, and the laser power P=2300W, the laser action time T=50s, and the laser spot diameter D=2.2mm are set according to the designed process parameters. Perform laser micro-area fixed-point melting, so that the raw material powder is melted and solidified at a set solidification rate to obtain a Ti-6Al-3Mo micro-area material; the Ti-6Al-4V micro-area material has a radius r=0.8mm.

FIG. 6 is an EDS scanning diagram of the Ti-6Al-3Mo microdomain material prepared in this example, FIG. 7a is a total distribution diagram of the content of each element in the Ti-6Al-3Mo microdomain material prepared in this example, and FIG. 7b is this example The EDS composition distribution diagram of Ti element content of the Ti-6Al-3Mo microdomain material prepared in this example, Fig. 7c is the EDS composition distribution diagram of Al element content of the Ti-6Al-3Mo microdomain material prepared in this example, and Fig. 7d is this example Figure 8a shows the EDS line scan macroscopic topography of the Ti-6Al-3Mo microdomain material prepared in this example, and Figure 8b shows the EDS line scan macroscopic topography of the Ti-6Al-3Mo microdomain material prepared in this example. EDS line scan data map of each element content of Ti-6Al-3Mo microdomain material. It can be seen from FIG. 6 , FIGS. 7 a to 7 d and FIGS. 8 a to 8 b that the distribution of Ti, Al and Mo in the Ti-6Al-3Mo microdomain material prepared in this example is uniform.

Example 6

The difference between this embodiment and Embodiment 4 is only that the laser power is adjusted to P=10000W. Figure 9 is a microstructure diagram of the Ti-6Al-3Mo microdomain material prepared in this example. It can be seen from Figure 9 that the Ti-6Al-3Mo microdomain material prepared in this example has a uniform structure and high density. It shows that the method of the present invention has good metallurgical effect on the new alloy material.

The application of the crucibleless laser micro-area metallurgy method based on the laser light-receiving path of the present invention in the rapid verification of computational materials science is described in detail through Examples 7 to 8.

Example 7

This embodiment includes the following steps:

Step 1. The Ti-6Al-4V powder with a mass purity of 99.5% and an average particle size of 120 μm, and an industrial pure B powder with a mass purity of 99.5% and an average particle size of 10 μm are designed according to Ti-6Al-4V-0.3B The ingredients are proportioned and 1% by mass of PVA glue is added for powder bonding and coating, ball milling and mixing in a planetary ball mill for 30 minutes, and then placed in a vacuum drying oven at a temperature of 70 ° C and a vacuum degree of -0.07MPa Dry for 8h under the same conditions, and then obtain the raw material powder;

对应的0<θ≤30°，或者

对应的30°<θ≤60°，或者

对应的60°<θ<90°； 所述激光作用时间和激光收光路径均通过激光波形进行控制；In step 2, the laser micro-area metallurgical parameters are combined and designed according to the characteristics of the raw material powder obtained in step 1, and a plurality of different laser micro-area metallurgy schemes including laser power, laser action time and laser light-receiving path are obtained, wherein, Laser power P can be segmented according to actual metallurgical conditions: low power range 100W≤P<2000W, medium power range 2000W≤P<6000W, high power range 6000W≤P≤10000W; laser action time T is segmented as: short time range 3ms≤T<30ms, medium time range 3ms≤T<3s, long time range 3s≤T≤50s; the laser waveform is a rectangular waveform or a right-angled trapezoidal waveform, and the right-angled trapezoidal waveform includes the peak power continuous phase and the power decay phase of the laser , and the right-angle trapezoidal waveform in the power decay stage is adjusted with the slope k of the hypotenuse and the angle θ of the hypotenuse, where k=tanθ, and the value range of the slope k is

The corresponding 0<θ≤30°, or

The corresponding 30°<θ≤60°, or

The corresponding 60°<θ<90°; the laser action time and the laser light receiving path are controlled by the laser waveform;

Step 3: Using the raw material powder obtained in step 1, carry out crucible-free laser micro-metallurgy respectively according to the multiple laser micro-area metallurgy schemes obtained in step 2, and use the method of laser melting pool fixed-point temperature measurement to measure each crucible-free laser micro-area. The molten pool temperature and the solidification parameters including the solidification rate and temperature gradient in the metallurgical process were measured. Micro-area materials with different structures and properties, and then establish the relationship between laser micro-area metallurgical parameters and micro-area materials, as follows: (1) In the low power range, it is easy to produce more metallurgical defects, such as cracks, pores, etc. problems, especially refractory alloy micro-area materials; in the medium power range, most of the micro-area materials have sufficient heat input to achieve strong convection in the molten pool. Micro-area materials with high quality and good formability; in the high power range, due to the large increase in the input heat source, especially for refractory/extremely refractory alloys, better metallurgical results can be obtained; but for most materials, the power is too high It will cause the formability of the micro-area material to be worse than that of the medium power range; (2) if the micro-area metallurgy is carried out in a short time range, there are metallurgical fusion defects for some materials; if the micro-area metallurgy is carried out in the medium time range, for most materials Micro-area materials with better metallurgical quality and formability can be obtained according to the reasonable combination of the combination; in the long-term metallurgy, the metallurgical effect of the material is significantly improved, but it has a negative effect on the materials that are easy to crack; (3) laser light-receiving In the path combination, the slow-speed waveform range realizes the slow-speed solidification of the molten pool, which is conducive to the formation of a microstructure composed of equilibrium phases; the medium-speed waveform range realizes the medium-speed solidification of the molten pool, and the micro-domain materials form equilibrium phases and non-equilibrium phases. The mixed structure of equilibrium phase composition; the rapid waveform range realizes the rapid solidification of the molten pool, which is conducive to the formation of non-equilibrium phase composition of micro-area materials; based on the relationship between the above laser micro-area metallurgical parameters and micro-area materials, according to the target product According to the solidification characteristics, the corresponding laser waveform is selected. By adjusting different solidification conditions and combining different metallurgical parameters, micro-domain materials with different structures and properties can be obtained;

Step 4. According to the relationship between the laser micro-area metallurgical parameters and the micro-area materials established in step 3, and according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 5. According to the laser micro-area metallurgy parameters designed in step 4, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 501: Lay the raw material powder on the horizontal titanium plate, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the oxygen in the laser working vacuum box. The content does not exceed 100ppm; the thickness of the laying is 2mm;

Step 502: According to the designed laser waveform, adjust the laser waveform to be a right-angled trapezoidal waveform and the slope of the right-angled trapezoidal waveform in the power decay stage k=3, corresponding to θ=72°, and set the laser power P=4000W according to the designed process parameters, and the laser The action time is T=20ms, the diameter of the laser spot is D=2.2mm, and the raw material powder laid on the horizontal titanium plate in step 501 is subjected to laser micro-area fixed-point melting by laser, so that the raw material powder is melted and solidified according to the set solidification rate. The Ti-6Al-4V-0.3B microdomain material 1 is obtained; the radius of the Ti-6Al-4V-0.3B1 microdomain material is r=0.8 mm.

Step 6: Observing and testing the microstructure and microhardness of the Ti-6Al-4V-0.3B micro-domain material 1 prepared in step 5, and then comparing the observation and testing results with computer materials science for Ti-6Al-4V-0.3B. The simulation results were compared and verified, and it was found that there were some differences between the two. Adjust the laser power P=1000W in the metallurgical parameters of the laser micro-area designed in step 5, and prepare the Ti-6Al-4V-0.3B micro-area material 2. Repeat Preparation process, observation and detection process and comparison and verification process, it is found that the observation and detection results are basically consistent with the simulation results of Ti-6Al-4V-0.3B by computer materials science after adjusting the metallurgical parameters of the laser micro-area. The specific process flow of this embodiment is shown in the figure. 10 shown.

FIG. 11a is a microstructure diagram of the Ti-6Al-4V-0.3B microdomain material 1 prepared in this example, and FIG. 11b is a microstructure diagram of the Ti-6Al-4V-0.3B microdomain material 2 prepared in this example. 11a and 11b, it can be seen that the microstructure and grain size of Ti-6Al-4V-0.3B microdomain materials prepared under different metallurgical parameters are significantly different.

For the microhardness and microstructure of Ti-6Al-4V-0.3B microdomain material 1 (ie material 1) and Ti-6Al-4V-0.3B microdomain material 2 (ie material 2) prepared in this example The TiB volume fraction was determined and compared with the simulation results of computational materials science, and the results are shown in Table 1 below.

Table 1

It can be seen from Table 1 that the method of the present invention affects the microstructure and improves the actual performance of the material by adjusting the metallurgical parameters of the laser micro-area, and compared with the simulation results of computational materials science, it is concluded that the microstructure prepared by the method of the present invention is used. The material properties of the area are basically close to the simulation results and have the same variation law, and the simulation results can be matched with the actual experimental results through the laser micro-area metallurgical parameters, indicating that the method of the present invention meets the rapid verification requirements of computational materials science.

Example 8

This embodiment includes the following steps:

Step 1. The Ti-6Al-4V powder with a mass purity of 99.5% and an average particle size of 120 μm and an industrial pure B powder with a mass purity of 99.5% and an average particle size of 10 μm are designed according to Ti-6Al-4V-0.5B The ingredients are proportioned and 1% by mass of PVA glue is added for bonding and coating, ball milling and mixing in a planetary ball mill for 30 minutes, and then placed in a vacuum drying oven, at a temperature of 80 ° C and a vacuum of -0.07 MPa. Dry under conditions for 8h to obtain raw material powder;

对应的0<θ≤30°，或者

对应的30°<θ≤60°，或者

对应的60°<θ<90°； 所述激光作用时间和激光收光路径均通过激光波形进行控制；In step 2, the laser micro-area metallurgical parameters are combined and designed according to the characteristics of the raw material powder obtained in step 1, and a plurality of different laser micro-area metallurgy schemes including laser power, laser action time and laser light-receiving path are obtained, wherein, Laser power P can be segmented according to actual metallurgical conditions: low power range 100W≤P<2000W, medium power range 2000W≤P<6000W, high power range 6000W≤P≤10000W; laser action time T is segmented as: short time range 3ms≤T<30ms, medium time range 3ms≤T<3s, long time range 3s≤T≤50s; the laser waveform is a rectangular waveform or a right-angled trapezoidal waveform, and the right-angled trapezoidal waveform includes the peak power continuous phase and the power decay phase of the laser , and the right-angle trapezoidal waveform in the power decay stage is adjusted with the slope k of the hypotenuse and the angle θ of the hypotenuse, where k=tanθ, and the value range of the slope k is

The corresponding 0<θ≤30°, or

The corresponding 30°<θ≤60°, or

The corresponding 60°<θ<90°; the laser action time and the laser light receiving path are controlled by the laser waveform;

Step 3: Using the raw material powder obtained in step 1, carry out crucible-free laser micro-metallurgy respectively according to the multiple laser micro-area metallurgy schemes obtained in step 2, and use the method of laser melting pool fixed-point temperature measurement to measure each crucible-free laser micro-area. The molten pool temperature and the solidification parameters including the solidification rate and temperature gradient in the metallurgical process were measured. Micro-area materials with different structures and properties, and then establish the relationship between laser micro-area metallurgical parameters and micro-area materials, as follows: (1) In the low power range, it is easy to produce more metallurgical defects, such as cracks, pores, etc. problems, especially refractory alloy micro-area materials; in the medium power range, most of the micro-area materials have sufficient heat input to achieve strong convection in the molten pool. Micro-area materials with high quality and good formability; in the high power range, due to the large increase in the input heat source, especially for refractory/extremely refractory alloys, better metallurgical results can be obtained; but for most materials, the power is too high It will cause the formability of the micro-area material to be worse than that of the medium power range; (2) if the micro-area metallurgy is carried out in a short time range, there are metallurgical fusion defects for some materials; if the micro-area metallurgy is carried out in the medium time range, for most materials Micro-area materials with better metallurgical quality and formability can be obtained according to the reasonable combination of the combination; in the long-term metallurgy, the metallurgical effect of the material is significantly improved, but it has a negative effect on the materials that are easy to crack; (3) laser light-receiving In the path combination, the slow-speed waveform range realizes the slow-speed solidification of the molten pool, which is conducive to the formation of a microstructure composed of equilibrium phases; the medium-speed waveform range realizes the medium-speed solidification of the molten pool, and the micro-domain materials form equilibrium phases and non-equilibrium phases. The mixed structure of equilibrium phase composition; the rapid waveform range realizes the rapid solidification of the molten pool, which is conducive to the formation of non-equilibrium phase composition of micro-area materials; based on the relationship between the above laser micro-area metallurgical parameters and micro-area materials, according to the target product According to the solidification characteristics, the corresponding laser waveform is selected. By adjusting different solidification conditions and combining different metallurgical parameters, micro-domain materials with different structures and properties can be obtained;

Step 4. According to the relationship between the laser micro-area metallurgical parameters and the micro-area materials established in step 3, and according to the organization and performance requirements of the target product, design the corresponding laser micro-area metallurgical parameters;

Step 5. According to the laser micro-area metallurgy parameters designed in step 4, use the raw material powder obtained in step 1 to carry out crucible-free laser micro-area metallurgy to prepare micro-area materials: the specific process of the crucible-free laser micro-area metallurgy is:

Step 501: Lay the raw material powder on the horizontal titanium plate in the form of a powder bed, and then send it into the laser working vacuum box of the laser micro-area metallurgical equipment, and then pass high-purity Ar gas into the laser working vacuum box and control the laser work. The oxygen content in the vacuum box does not exceed 100ppm; the thickness of the laying is 2mm;

Step 502: Adjust the laser waveform to be a right-angled trapezoidal waveform according to the designed laser waveform and the slope of the right-angled trapezoidal waveform in the power decay stage k=3, corresponding to θ=72°, and set the laser power P=3000W according to the designed process parameters, the laser action Time T=20ms, laser spot diameter D=2.2mm, use laser to perform laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in step 501, so that the raw material powder is melted and then solidified according to the set solidification rate to obtain Ti-6Al-4V-0.5B microdomain material; the radius r=0.8mm of the Ti-6Al-4V-0.5B microdomain material;

Step 6: Observing and testing the microstructure and microhardness of the Ti-6Al-4V-0.5B micro-domain material prepared in step 5, and then comparing the observation and testing results with computer materials science to determine the microstructure of Ti-6Al-4V-0.5B. The simulation results are compared and verified, and it is found that the two are basically consistent.

Fig. 12 is a microstructure diagram of the Ti-6Al-4V-0.5B microdomain material prepared in this example. From the comparison between Fig. 12 and Fig. 11a and Fig. 11b, it can be seen that the Ti-6Al prepared by adding boron element in this example The second phase precipitate and structure of the -4V-0.5B microdomain material are obviously different from those of the Ti-6Al-4V-0.3B microdomain material prepared in Example 7.

The microhardness and TiB volume fraction in the microstructure of the Ti-6Al-4V-0.5B microdomain material (ie, material 1) prepared in this example were measured, and compared with the simulation results of computational materials science. The results are as follows shown in Table 2.

Table 2

As can be seen from Table 2, the properties of the micro-domain materials prepared by the method of the present invention are basically consistent with the simulation results, indicating that the method of the present invention satisfies the rapid verification requirements of computational materials science.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any way. Any simple modifications, changes and equivalent changes made to the above embodiments according to the technical essence of the invention still fall within the protection scope of the technical solutions of the present invention.

Claims (6)

1. A crucible-free laser micro-area metallurgy method based on laser light receiving path regulation is characterized by comprising the following steps:

step one, according to the requirement of the powder particle size range of a powder bed of laser micro-area metallurgical equipment, performing powder proportioning mixing according to the design components of a target product by adopting an element mixing method, and then drying to obtain raw material powder;

step two, carrying out combined design on the laser micro-area metallurgical parameters according to the characteristics of the raw material powder obtained in the step one to obtain a plurality of different laser micro-area metallurgical schemes which respectively comprise laser power, laser action time and laser light receiving paths; the laser action time and the laser light receiving path are controlled by laser waveforms;

step three, adopting the raw material powder obtained in the step one, respectively carrying out crucible-free laser micro-area metallurgy according to a plurality of laser micro-area metallurgy schemes obtained in the step two, measuring the temperature of a molten pool and solidification parameters including solidification temperature and temperature gradient in the process of each crucible-free laser micro-area metallurgy by adopting a laser molten pool fixed-point temperature measurement method, inspecting the influence of laser power and laser action time on the convection degree in the molten pool and the influence of a laser light receiving path on the solidification condition of the molten pool, obtaining micro-area materials with different structures and performances, and then establishing the relation between the laser micro-area metallurgy parameters and the micro-area materials;

step four, designing corresponding laser micro-area metallurgical parameters according to the relation between the laser micro-area metallurgical parameters and the micro-area materials established in the step three and the requirements on the structure and the performance of the target product;

step five, according to the laser micro-area metallurgical parameters designed in the step four, performing crucible-free laser micro-area metallurgy by adopting the raw material powder obtained in the step one to prepare a micro-area material: the specific process of the crucible-free laser micro-area metallurgy comprises the following steps:

step 501, laying raw material powder on a horizontal carrier; the thickness of the paving is 2 mm-20 mm;

and 502, setting laser power and laser action time, setting a solidification parameter by adjusting a laser waveform, and then carrying out laser micro-area fixed-point melting on the raw material powder laid on the horizontal carrier in the step 501 by adopting laser, so that the raw material powder is solidified according to the set solidification parameter after being melted, and thus obtaining a micro-area material.

2. The crucible-free laser micro-area metallurgy method based on laser beam receiving path regulation and control of claim 1, wherein in the first step, the mass purity of each component powder of the target product is more than 99%, and the particle size ranges from 3 μm to 150 μm.

3. The crucible-free laser micro-area metallurgy method based on laser beam receiving path regulation and control as claimed in claim 1, wherein the element mixing method in the step one is a direct mixing method, a method combining mechanical mixing and ball milling treatment, or a bonding coating method.

4. The crucible-free laser micro-area metallurgy method based on laser beam receiving path regulation and control of claim 1, wherein the drying device in the first step is a vacuum drying furnace, the temperature of the drying process is 70-125 ℃, the time is 2-8 h, and the vacuum degree is-0.05 MPa-0.085 MPa.

5. The crucible-free laser micro-area metallurgy method based on laser beam receiving path control according to claim 1, wherein in step 502The laser power is 100W-10000W, the laser action time is 5 ms-50 s, the laser waveform is a rectangular waveform or a right trapezoid waveform, the right trapezoid waveform comprises a peak power continuous stage and a power attenuation stage of the laser, the right trapezoid waveform of the power attenuation stage is adjusted along with an inclined edge slope k and an inclined edge angle theta, wherein k is tan theta, and the value range of the slope k is

Corresponding to 0<Theta is less than or equal to 30 DEG, or

Corresponding 30 °<Theta is less than or equal to 60 DEG, or

Corresponding 60 degree<θ<90°。

6. The application of the crucible-free laser micro-area metallurgy method based on laser collection path regulation and control in the rapid verification of the computational materials as claimed in any one of claims 1 to 5 is characterized in that the specific process of the application is as follows: firstly, setting a laser light receiving path by adjusting the laser waveform in laser micro-area metallurgical equipment according to the solidification condition designed by computational materials science on a material to be researched to ensure that the solidification condition is consistent to obtain laser micro-area metallurgical parameters, then preparing the material to be researched by a crucible-free laser micro-area metallurgical method, measuring the tissue and performance parameters of the material to be researched, comparing and verifying the tissue and performance parameters with the simulation result of the computational materials science to determine the accuracy of the simulation result of the tissue and performance parameters of the material to be researched by the computational materials science, modifying the calculation parameters according to the deviation of the calculation result and the test result, carrying out feedback adjustment on the laser micro-area metallurgical parameters, and repeating the preparation process, the measurement process and the comparison and verification process in sequence until the tissue and performance parameters of the material to be researched are consistent with the simulation result of the computer materials science.

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