CN111778503B - Crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control and application - Google Patents

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

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CN111778503B
CN111778503B CN202010692217.9A CN202010692217A CN111778503B CN 111778503 B CN111778503 B CN 111778503B CN 202010692217 A CN202010692217 A CN 202010692217A CN 111778503 B CN111778503 B CN 111778503B
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CN111778503A (en
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张凤英
王坤
王红波
孙志平
胡腾腾
王刚
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Changan University
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C24/00—Coating starting from inorganic powder
    • C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
    • C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C24/00—Coating starting from inorganic powder
    • C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
    • C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
    • C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
    • C23C24/106—Coating with metal alloys or metal elements only
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Abstract

The invention discloses a crucible-free laser micro-area metallurgy method based on laser light receiving path regulation, which comprises the following steps: firstly, preparing raw material powder; designing a plurality of laser micro-area metallurgy schemes; thirdly, establishing a relation between the laser micro-area metallurgical parameters and the micro-area materials; fourthly, designing corresponding laser micro-area metallurgical parameters according to the structure and performance requirements of the target product; fifthly, preparing a micro-area material; in addition, the invention also discloses application of the crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control in rapid verification of computational materials science. The method utilizes laser to enable powder around a micro-area molten pool to generate a metallurgical crucible, realizes matrix-free and crucible-free short-period micro-area metallurgy, adjusts laser waveform according to the characteristics of raw material powder to determine a laser light receiving path, realizes controllability of a cooling and solidifying stage of the micro-area metallurgy, and controls the phase structure of a micro-area material; the application of the invention provides an efficient and quick verification method for the computational materials science.

Description

Crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control and application
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control and application thereof.
Background
From the first stone age to the modern new material age, material innovation is the technical key of subversive generations of development. For the world, countries that have developed new materials first will be in the forefront of the industrial revolution in the 21 st century. Therefore, how to efficiently develop innovative materials in a short time and accelerate the development process of new materials becomes the direction of efforts in various countries. However, in the process of accelerating the development of new materials, the following bottleneck problems are encountered and need to be solved:
(1) the existing research and development of materials to new materials depend on the existing scientific experience and trial and error under more conditions, the whole process is long in period and low in efficiency, and particularly, when a traditional smelting method is adopted for testing, the problems of long period, complex research process, high investment cost, extremely low efficiency and the like are reflected;
(2) the development of computational materials science is promoted by the difficulties of tests and alloy smelting, the tissues and the properties of different new materials can be rapidly calculated by using the computational materials science method, the influence of the obtained solidification parameters on the tissues and the properties of the materials is calculated, and the relationship between the tissues and the properties of the materials and the solidification parameters is established. However, how to verify the rapidly designed materials and their correlation with solidification conditions becomes a bottleneck to be broken through urgently. Particularly in the field of refractory alloys, due to the high melting point of the refractory alloys, on one hand, proper materials are not used as a melting crucible, and on the other hand, in the process of preparing the materials, because convection in a melting pool is insufficient, the materials are difficult to alloy, the refractory alloy materials are difficult to prepare, so that the calculation result cannot be verified, the deep development in the field of computational materials is greatly hindered, and the development process of new materials is restricted.
Based on the above analysis, a new technology capable of realizing rapid preparation of materials and solving the problem of melting of high-melting-point refractory materials (such as crucible selection, bath convection and metallurgical uniformity) is urgently needed, and particularly, a technical method which can simultaneously meet the requirements of rapid metallurgy of continuously adjustable solidification conditions and efficiently, greenly and accurately meet the verification requirements of computational materials is needed.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a crucible-free laser micro-area metallurgy method based on laser beam path regulation and control, aiming at the defects of the prior art. The method utilizes the high energy of laser to enable powder around a micro-area molten pool to generate a 'metallurgical crucible' by self, so that the micro-area molten pool realizes matrix-free and crucible-free short-period micro-area metallurgy, and establishes the relation between the laser micro-area metallurgical parameters and the micro-area material structure and performance, thereby regulating the laser waveform according to the characteristics of raw material powder to determine the laser beam receiving path, improving the controllability of the whole micro-area metallurgy cooling and solidifying stage, simultaneously being beneficial to the phase structure transformation of alloy, and further obtaining the micro-area material with uniform tissue distribution.
In order to solve the technical problems, the invention adopts the technical scheme that: 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 the solidification temperature and the temperature gradient in the metallurgical process of each crucible-free laser micro-area 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.
The powder particle size range requirement of the powder laying of the laser micro-area metallurgical equipment adopted by the invention is as follows: the powder should have a reasonable particle size range. When the particle size of the powder is too small, the powder adsorbs each other to generate agglomeration, the smaller the particle size of the powder is, the larger the specific surface area of the powder is, the higher the specific surface energy is, the powder spreading effect of the powder is poor, the overheating phenomenon is easy to occur in the laser action process, the molten drop is caused to splash, and the quality of the micro-area material is influenced; when the particle size of the powder is large, in the laser action process, the effective energy of laser cannot meet the requirement of powder particle melting, the powder is not completely melted, and the compactness and the mechanical property of the micro-area material are seriously influenced.
According to the requirement of the powder particle size range laid by laser micro-area metallurgical equipment powder, the powder of each component of a target product is proportioned, mixed and dried to be used as raw material powder, and then the micro-area material is prepared by adopting a laser micro-area metallurgical method; meanwhile, the laser of high-energy beams is used as a raw material powder smelting input heat source, so that strong convection is realized in the whole molten pool melt, the molten pool temperature capable of fully melting the powder material is obtained, the set process parameters are combined, the smelting time is accurately regulated and controlled through the laser action time, more uniform and sufficient metallurgical effect is realized, and particularly, the refractory alloy with uniform components can be obtained for the refractory alloy material. Therefore, different from the prior art that laser waveform is directly selected for heating and smelting, the invention firstly carries out combined design on laser micro-area metallurgical parameters including laser power, laser action time and laser light receiving path (the laser action time and the laser light receiving path are both controlled by the laser waveform which determines the laser light receiving path, namely the solidification condition after smelting the raw material powder) according to the characteristics of the raw material powder, obtains a plurality of laser micro-area metallurgical schemes and respectively carries out crucible-free laser micro-area metallurgy, measures and inspects the influence of the laser power and the laser action time on the convection degree in a molten pool and the influence of the laser light receiving path on the solidification condition of the molten pool, obtains micro-area materials with different tissues and performances, and then establishes the relationship between the laser micro-area metallurgical parameters and the micro-area materials, based on the parameters, corresponding laser micro-area metallurgical parameters are designed according to the tissue and performance requirements of the target product, crucible-free laser micro-area metallurgy is carried out, and the micro-area material is prepared. The method designs the laser waveform in advance according to the characteristics of the raw material powder, so that the laser beam repeatedly acts on a molten pool formed by powder melting for many times, the controllability of the whole micro-area metallurgy heating melting and cooling solidification stages is improved, meanwhile, the phase structure transformation of refractory alloy is facilitated, the duration of the metallurgy action is flexibly controlled through the adjustment of the laser micro-area metallurgy parameters with high maneuverability, the controllability of the size of the molten pool from micron to millimeter is realized, and the micro-area material with uniform size and uniform tissue distribution is obtained; meanwhile, the restriction of the crucible and the base body on the metallurgical condition is removed, and a zero-pollution environment is provided for the whole laser micro-area metallurgical process.
The crucible-free laser micro-area metallurgy method based on laser beam-receiving path regulation is characterized in that in the step one, the mass purity of each component powder of the target product is more than 99%, and the particle size ranges from 3 micrometers to 150 micrometers.
The crucible-free laser micro-area metallurgy method based on laser beam receiving path regulation is characterized in that 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. The direct mixing method is that the element powder of the material is directly mixed mechanically after being proportioned according to the designed components; the method combining mechanical mixing and ball milling treatment comprises the steps of proportioning and mechanically mixing the powder of each component according to the designed components, and then carrying out ball milling treatment by adopting a ball mill; the bonding coating method is that the powder of each component of the material is proportioned according to the designed components, PVA (polyvinyl alcohol) glue is added as a powder adhesive, and then ball milling is carried out until the materials are uniformly mixed. The element mixing method is various and is suitable for various materials.
The crucible-free laser micro-area metallurgical method based on laser light receiving path regulation is characterized in that in the step one, the equipment adopted for drying treatment is a vacuum drying furnace, the temperature of the drying treatment is 70-125 ℃, the time is 2-8 h, and the vacuum degree is-0.05 MPa-0.085 MPa. The optimized drying device and the optimized drying process parameters effectively remove the water adsorbed in the powder of each component 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.
The crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control is characterized in that in the step 502, the 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 in 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
Figure BDA0002589706400000051
Corresponding to 0<Theta is less than or equal to 30 DEG, or
Figure BDA0002589706400000052
Corresponding 30 °<Theta is less than or equal to 60 DEG, or
Figure BDA0002589706400000053
Corresponding 60 degree<θ<At 90 deg.. Wherein
Figure BDA0002589706400000054
Corresponding to 0<Theta is less than or equal to 30 degrees, so that the slow solidification of the molten pool is realized (as shown in figure 1 a), the structure composed of equilibrium phases is formed by the micro-area material,
Figure BDA0002589706400000055
corresponding 30 °<Theta is less than or equal to 60 degrees, the medium-speed solidification of a molten pool is realized (as shown in figure 1 b), the micro-area material forms a mixed structure consisting of an equilibrium phase and a non-equilibrium phase,
Figure BDA0002589706400000056
corresponding 60 degree<θ<The rapid solidification of the molten pool is realized at 90 degrees (as shown in figure 1 c), which is beneficial to forming a structure consisting of a non-equilibrium phase by the micro-area material, thereby being beneficial to selecting a corresponding laser waveform according to the solidification characteristic of a target product, obtaining the micro-area alloy material with different structures and performances by adjusting different solidification parameters, adapting to the requirements of laying powder with different characteristics and improving the application range of the method of the invention.
Theoretically, the laser power P is increased, the laser action time T is prolonged, the molten pool is enabled to obtain sufficient heat input, strong convection in the molten pool is realized, the structure performance of the prepared micro-area material is excellent, but the molten pool is overheated due to the fact that the laser power P is too high, the laser action time T is too long, molten drops splash, and the surface quality and the internal structure quality of the micro-area material are affected. Therefore, the optimal process parameters give consideration to sufficient heat input and proper convection in the molten pool, so that the prepared micro-area material has excellent microstructure and mechanical properties.
In addition, the invention also provides application of the crucible-free laser micro-area metallurgy method based on laser light receiving path regulation and control in the rapid verification of computational materials, which is characterized in that the application process comprises the following steps: firstly, setting a laser light receiving path by adjusting laser waveform in laser micro-area metallurgical equipment according to the solidification condition designed by computational materials science on a material to be researched so as to ensure that the solidification conditions are consistent and obtain laser micro-area metallurgical parameters, then preparing the micro-area material by a crucible-free laser micro-area metallurgy method, measuring the tissue and performance parameters of the micro-area material, comparing and verifying the tissue and performance parameters with the simulation result of computational materials science, so as to determine the accuracy of the simulation result of the organization and performance parameters of the material to be researched by the computational materials science, modify the computational parameters according to the deviation of the computational results and the test results, and feedback adjustment is carried out on the metallurgical parameters of the laser micro-area, and the preparation process, the measurement process and the comparison and verification process are sequentially repeated until the tissue and performance parameters of the micro-area material are consistent with the simulation result of the computer material science.
At present, the field of computational materials has the defects that the calculated refractory/extremely-refractory materials are difficult to verify in practical experiments and low in verification efficiency. Because the preparation method of the crucible-free laser micro-area material realizes the rapid preparation of the micro-area material, the corresponding micro-area material is rapidly prepared by adopting the method according to the material structure and the performance designed by the computational materials, and then the performance verification is carried out: if the elastic modulus and the microhardness are rapidly verified by a micro-indentation test method and a nano-indentation test method; rapidly verifying the width of the crystal grain through Image pro software; the grain growth mode was rapidly verified by electron back-scattering diffraction. The application meets the rapid verification requirement of the computing materials science, and provides an efficient and accurate verification technology for the field of the computing materials science.
Compared with the prior art, the invention has the following advantages:
1. according to the invention, the laser micro-area metallurgical parameters are detected by adopting a laser molten pool fixed-point temperature measurement method, and the relation between the laser micro-area metallurgical parameters and the micro-area material structure and performance is established, so that the laser light receiving path is determined by adjusting the laser waveform according to the characteristics of the raw material powder, the controllability of the whole micro-area metallurgical cooling and solidification stage is improved, meanwhile, the phase structure transformation of refractory alloy is facilitated, and the micro-area material with uniformly distributed structures is obtained.
2. The invention adopts the laser micro-area metallurgy method to prepare the micro-area material, utilizes the characteristic that the high energy of the laser can fully melt the metal powder, leads the powder around the micro-area molten pool to generate a 'metallurgical crucible', utilizes the characteristic that the powder around the micro-area carries out large heat dissipation, leads the micro-area molten pool to realize matrix-free and crucible-free short-period micro-area metallurgy, simultaneously removes the limitation of the crucible and the matrix material on the metallurgy condition, and provides zero pollution environment for the laser micro-area metallurgy process.
3. The invention adopts high-energy beam laser as raw material powder smelting input heat source, realizes strong convection in the whole molten pool melt, combines set process parameters, and precisely regulates and controls smelting time through laser pulse width, thereby realizing more uniform and sufficient metallurgical effect.
4. The micro-area material prepared by the method has the advantages of uniform and smooth surface, no air holes, no oxidation, uniform product material, good metallurgical quality, uniform distribution of product crystal grains and components, and realization of metallurgy of high-hardness and high-melting-point materials.
5. The preparation method disclosed by the invention is simple, efficient, energy-saving, green and environment-friendly, is suitable for the field of high-flux micro-area material preparation, and has a wide application prospect in the field of material genetic engineering.
6. The preparation method disclosed by the invention is simple in process and quick in response, is applied to the field of computational materials, overcomes the defects of difficulty in verification and low efficiency of a research object material in an actual experiment, and is wide in application range, efficient and accurate in verification.
7. The preparation method not only realizes the rapid micro-area preparation of the novel material, efficiently obtains the novel material in time and shortens the preparation period, but also obtains the correlation between the structure performance and the solidification rate of the alloy material, thereby realizing the acquisition of the micro-area material with continuously adjustable structure and performance through different solidification rates.
8. The application of the invention provides an efficient and rapid verification method for the computing materials science, and the verification efficiency is obviously improved compared with the traditional smelting method.
The technical solution of the present invention is further described in detail by the accompanying drawings and examples.
Drawings
FIG. 1a is a schematic representation of a slow setting right angle trapezoidal waveform employed in the present invention.
FIG. 1b is a schematic illustration of a moderate speed coagulating right angle trapezoidal waveform employed in the present invention.
FIG. 1c is a schematic representation of a rapidly solidified right angle trapezoidal waveform employed in the present invention.
FIG. 2 is a microstructure of Ti-6Al-4V domain material prepared in example 1 of the present invention.
FIG. 3 is a microstructure of Ti-6Al-4V domain material prepared in example 2 of the present invention.
FIG. 4 is a microstructure of Ti-6Al-4V domain material prepared in example 3 of the present invention.
FIG. 5 is a microstructure of Ti-6Al-4V domain material prepared in example 4 of the present invention.
FIG. 6 is an EDS scan of Ti-6Al-3Mo micro-domain material prepared in example 5 of the invention.
FIG. 7a is a total distribution diagram of the contents of the elements in the Ti-6Al-3Mo micro-domain material prepared in example 5 of the present invention.
FIG. 7b is an EDS composition distribution diagram of Ti element content of Ti-6Al-3Mo micro-domain material prepared in example 5 of the present invention.
FIG. 7c is an EDS composition profile of Al content for Ti-6Al-3Mo micro-domain material prepared in example 5 of the present invention.
FIG. 7d is an EDS composition distribution diagram of the Mo element content of Ti-6Al-3Mo micro-domain material prepared in example 5 of the invention.
FIG. 8a is an EDS line scan macro topography of Ti-6Al-3Mo micro-area material prepared in example 5 of the present invention.
FIG. 8b is a graph of EDS line scan data for Ti-6Al-3Mo micro-domain material prepared in example 5 of the present invention for the content of each element.
FIG. 9 is a microstructure of Ti-6Al-3Mo domain material prepared in example 6 of this invention.
FIG. 10 is a process flow diagram of example 7 of the present invention.
FIG. 11a is a microstructure diagram of the Ti-6Al-4V-0.3B domain material 1 prepared in example 7 of the present invention.
FIG. 11B is a microstructure diagram of the Ti-6Al-4V-0.3B domain material 2 prepared in example 7 of the present invention.
FIG. 12 is a microstructure of Ti-6Al-4V-0.5B domain material prepared in example 8 of the present invention.
Detailed Description
The crucible-free laser micro-area metallurgy method based on laser light receiving path regulation is described in detail through embodiments 1 to 6.
Example 1
The embodiment comprises the following steps:
step one, industrial pure Ti powder with the mass purity of 99% and the average grain diameter of 130 microns, industrial pure Al powder with the mass purity of 99% and the average grain diameter of 10 microns and industrial pure V powder with the mass purity of 99% and the grain diameter of 30 microns are proportioned according to the design components of Ti-6Al-4V and are directly mixed, then the mixture is placed in a vacuum drying furnace and dried for 2 hours under the conditions that the temperature is 125 ℃ and the vacuum degree is-0.085 MPa, and raw material powder is obtained;
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, and obtaining a plurality of laser micro-area metallurgical schemes which are different and respectively comprise laser power and laser action time and laser light receiving paths, wherein the laser power P can be segmented into the following steps according to actual metallurgical conditions: low power range 100W ≦ P<2000W, medium power range 2000W ≤ P<6000W, wherein P is more than or equal to 6000W and is more than or equal to 10000W in a high power range; the laser action time T is segmented into: short time range of 3ms to T<30ms, and T is more than or equal to 3ms in the middle time range<T is more than or equal to 3s and less than or equal to 50s within a long time range of 3 s; the laser waveform is a rectangular waveform or a right-angle trapezoidal waveform, the right-angle trapezoidal waveform comprises a peak power continuous stage and a power attenuation stage of the laser, and the power attenuation stageThe right trapezoid waveform in the reduction stage is adjusted along with the slope k of the hypotenuse and the angle theta of the hypotenuse, wherein k is tan theta, and the value range of the slope k is
Figure BDA0002589706400000101
Corresponding to 0<Theta is less than or equal to 30 DEG, or
Figure BDA0002589706400000102
Corresponding 30 °<Theta is less than or equal to 60 DEG, or
Figure BDA0002589706400000103
Corresponding 60 degree<θ<90 degrees; 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 speed and temperature gradient in the metallurgical process of each crucible-free laser micro-area by adopting a laser molten pool fixed-point temperature measurement method, investigating 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 rate 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, wherein the specific steps are as follows: (1) in a low power range, more metallurgical defects such as cracks, air holes and the like are easy to generate, and particularly, the refractory alloy micro-area material is adopted; in the medium power range, most micro-area materials have sufficient heat input, so that strong convection in a molten pool is realized, and the micro-area materials with better metallurgical quality and good formability can be obtained according to reasonable matching of combination; in a high power range, due to the great promotion of an input heat source, a better metallurgy effect can be obtained particularly for refractory/refractory alloys; however, for most materials, too high a power will result in a micro-domain material with poor formability in the medium power range; (2) micro-area metallurgy is carried out in a short time range, and metallurgical fusion defects exist in partial materials; micro-area metallurgy is carried out within a middle time range, and for most materials, micro-area materials with better metallurgical quality and formability can be obtained according to reasonable collocation of combination; the metallurgical effect of the material is obviously improved in the long-time metallurgy, but the material has negative effect on the easily-cracked material; (3) in the laser light-receiving path combination, the slow solidification of a molten pool is realized within the slow waveform range, so that the micro-area material can form a structure consisting of a balance phase; the medium-speed wave form range realizes medium-speed solidification of a molten pool, and the micro-area material forms a mixed structure consisting of an equilibrium phase and a non-equilibrium phase; the rapid wave form range realizes the rapid solidification of the molten pool, and is beneficial to the micro-area material to form a structure consisting of non-equilibrium phases; by integrating the relationship between the laser micro-area metallurgical parameters and the micro-area materials, selecting corresponding laser waveforms according to the solidification characteristics of target products, and combining different metallurgical parameters by adjusting different solidification conditions, the micro-area materials with different tissues and properties can be obtained;
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 of 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 titanium plate, then sending the raw material powder into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 20 mm;
502, adjusting the laser waveform to be a right trapezoid waveform according to the designed laser waveform and adjusting the slope of the right trapezoid waveform in the power attenuation stage
Figure BDA0002589706400000111
Corresponding theta is 30 degrees, the laser power P is 2300W according to the designed process parameters, the laser action time T is 50s, and the laser spot diameter D is 2300W2.2mm, performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 501 by adopting laser, so that the raw material powder is solidified according to a set solidification rate after being melted, and obtaining a Ti-6Al-4V micro-area material; the radius r of the Ti-6Al-4V micro-area material is 0.8 cm.
FIG. 2 is a microstructure diagram of the Ti-6Al-4V domain material prepared in this example, and it can be seen from FIG. 2 that the Ti-6Al-4V domain material prepared in this example is a uniformly distributed α phase and a residual β phase of the slender strips.
The slope k of the rectangular trapezoid waveform in the power attenuation stage in step 502 of this embodiment may also be a range of slow waveforms
Figure BDA0002589706400000121
In addition to
Figure BDA0002589706400000122
The corresponding theta can also be 0<And theta ≦ 30 deg. other than 30 deg..
Example 2
The embodiment comprises the following steps:
step one, mixing industrial pure Ti powder with the mass purity of 99% and the particle size of 130 microns, industrial pure Al powder with the mass purity of 99% and the particle size of 10 microns and industrial pure V powder with the mass purity of 99% and the particle size of 30 microns according to the design component proportion of Ti-6Al-4V, directly mixing, then placing in a vacuum drying furnace, and drying for 2 hours under the conditions that the temperature is 125 ℃ and the vacuum degree is-0.085 MPa to obtain raw material powder;
step two, 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 of the embodiment 1 and according to the structure and performance requirements of a target product;
step three, according to the laser micro-area metallurgical parameters designed in the step two, 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:
301, laying raw material powder on a horizontal titanium plate, then sending the raw material powder into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 20 mm;
step 302, adjusting the laser waveform to be a right trapezoid waveform according to the designed laser waveform, setting the slope k of the right trapezoid waveform at the power attenuation stage to be 1, setting the corresponding theta to be 45 degrees, setting the laser power P to be 2300W according to the designed process parameters, setting the laser action time T to be 25s, setting the laser spot diameter D to be 2.2mm, and performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 301 by adopting laser to solidify the raw material powder according to the set solidification rate after melting to obtain a Ti-6Al-4V micro-area material; the radius r of the Ti-6Al-4V micro-area material is 0.6 cm.
FIG. 3 is a microstructure diagram of the Ti-6Al-4V domain material prepared in this example, and it can be seen from FIG. 3 that the Ti-6Al-4V domain material prepared in this example is a uniformly distributed and coexisting slender plate α phase, martensite α' phase and matrix β phase.
The slope k of the rectangular trapezoid waveform in the power attenuation stage in step 502 of this embodiment may also be a medium-speed waveform range
Figure BDA0002589706400000131
Wherein, in addition to k being 1, θ is 30 °<And theta ≦ 60 ° other than theta 45 °.
Example 3
The embodiment comprises the following steps:
step one, industrial pure Ti powder with the mass purity of 99% and the average grain diameter of 130 microns, industrial pure Al powder with the mass purity of 99% and the average grain diameter of 10 microns and industrial pure V powder with the mass purity of 99% and the average grain diameter of 30 microns are proportioned according to the design components of Ti-6Al-4V and are directly mixed, then the mixture is placed in a vacuum drying furnace and dried for 8 hours under the conditions that the temperature is 120 ℃ and the vacuum degree is-0.07 MPa, and raw material powder is obtained;
step two, 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 of the embodiment 1 and according to the structure and performance requirements of a target product;
step three, according to the laser micro-area metallurgical parameters designed in the step two, performing crucible-free laser micro-area metallurgy by adopting the raw material powder obtained in the step one, and preparing a micro-area material: the specific process of the crucible-free laser micro-area metallurgy comprises the following steps:
301, laying raw material powder on a horizontal titanium plate, then sending the raw material powder into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 20 mm;
step 302, adjusting the laser waveform to be a right-angled trapezoidal waveform according to the designed laser waveform, setting the slope k of the right-angled trapezoidal waveform at the power attenuation stage to be 2, setting the corresponding theta to be 63.4 degrees, setting the laser power P to be 2300W according to the designed process parameters, setting the laser action time T to be 25s, setting the laser spot diameter D to be 2.2mm, and performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 301 by adopting laser to solidify the raw material powder at a set solidification rate after melting to obtain a Ti-6Al-4V micro-area material; the radius r of the Ti-6Al-4V micro-area material is 0.4 cm.
FIG. 4 is a microstructure diagram of the Ti-6Al-4V domain material prepared in this example, and it can be seen from FIG. 4 that the Ti-6Al-4V domain material prepared in this example is uniformly distributed needle-shaped martensite alpha' and residual beta phase.
The slope k of the rectangular trapezoid waveform of the power attenuation stage in step 502 of this embodiment may also be a fast waveform range
Figure BDA0002589706400000141
Wherein, in addition to k being 2, θ is 60 °<θ<The value of 90 ° other than θ of 63.4 °.
Comparing fig. 2, fig. 3 and fig. 4, it can be known that adjusting the laser waveform in the laser micro-zone metallurgy preparation process is helpful to expand the solidification parameter range of laser smelting while improving the controllability of the whole micro-zone metallurgy cooling solidification stage, and regulate and control the tissue of the micro-zone material, so as to obtain micro-zone materials with different properties, and expand the application range of the micro-zone material.
Example 4
The difference between this example and example 3 is: the laser waveform is adjusted to a rectangular waveform, i.e., θ is 90 °.
Fig. 5 is a microstructure diagram of the Ti-6Al-4V micro-domain material prepared in this embodiment, and it can be seen from fig. 5 that the structure of the Ti-6Al-4V micro-domain material prepared in this embodiment is uniform and has high density, the solidification condition in this embodiment is substantially close to that of the rapid solidification waveform in embodiment 3, and the obtained structure is the same, but since the laser waveform adopted in this embodiment is a rectangular waveform, the solidification speed is extremely fast, a finer needle-like martensite structure is clearly shown, and the overall metallurgical effect of the material is good.
Example 5
The embodiment comprises the following steps:
step one, mixing industrial pure Ti powder with the mass purity of 99.5% and the particle size of 150 microns, industrial pure Al powder with the mass purity of 99% and the particle size of 15 microns and industrial pure Mo powder with the mass purity of 99.5% and the particle size of 3 microns according to the design component proportion of Ti-6Al-3Mo, mechanically mixing the materials for about 30min in a planetary ball mill, then placing the materials in a vacuum drying furnace, and drying the materials for 3h under the conditions that the temperature is 70 ℃ and the vacuum degree is-0.05 MPa 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, and obtaining a plurality of different laser micro-area metallurgical schemes which respectively comprise laser power, laser action time and a laser light receiving path, wherein the laser power P can be segmented into the following steps according to actual metallurgical conditions: low power range 100W ≦ P<2000W, medium power range 2000W ≤ P<6000W, wherein P is more than or equal to 6000W and is more than or equal to 10000W in a high power range; the laser action time T is segmented into: short time range of 3ms to T<30ms, and T is more than or equal to 3ms in the middle time range<T is more than or equal to 3s and less than or equal to 50s within a long time range of 3 s; the laser waveform is a rectangular waveform or a right trapezoid waveformThe right-angle trapezoidal waveform comprises a peak power continuous stage and a power attenuation stage of laser, and the right-angle trapezoidal 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
Figure BDA0002589706400000151
Corresponding to 0<Theta is less than or equal to 30 DEG, or
Figure BDA0002589706400000152
Corresponding 30 °<Theta is less than or equal to 60 DEG, or
Figure BDA0002589706400000153
Corresponding 60 degree<θ<90 degrees; 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 speed and temperature gradient in the metallurgical process of each crucible-free laser micro-area by adopting a laser molten pool fixed-point temperature measurement method, investigating 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 rate 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, wherein the specific steps are as follows: (1) in a low power range, more metallurgical defects such as cracks, air holes and the like are easy to generate, and particularly, the refractory alloy micro-area material is adopted; in the medium power range, most micro-area materials have sufficient heat input, so that strong convection in a molten pool is realized, and the micro-area materials with better metallurgical quality and good formability can be obtained according to reasonable matching of combination; in a high power range, due to the great promotion of an input heat source, a better metallurgy effect can be obtained particularly for refractory/refractory alloys; however, for most materials, too high a power will result in a micro-domain material with poor formability in the medium power range; (2) micro-area metallurgy is carried out in a short time range, and metallurgical fusion defects exist in partial materials; micro-area metallurgy is carried out within a middle time range, and for most materials, micro-area materials with better metallurgical quality and formability can be obtained according to reasonable collocation of combination; the metallurgy effect of the material is obviously improved in a long-time range, but the metallurgy effect has a negative effect on the easily-cracked material; (3) in the laser light-receiving path combination, the slow solidification of a molten pool is realized within the slow waveform range, so that the micro-area material can form a structure consisting of a balance phase; the medium-speed wave form range realizes medium-speed solidification of a molten pool, and the micro-area material forms a mixed structure consisting of an equilibrium phase and a non-equilibrium phase; the rapid wave form range realizes the rapid solidification of the molten pool, and is beneficial to the micro-area material to form a structure consisting of non-equilibrium phases; the relation between the laser micro-area metallurgical parameters and the micro-area materials is integrated, the corresponding laser waveform is selected according to the solidification characteristics of the target product, and the micro-area materials with different structures and performances can be obtained by adjusting different solidification conditions and combining different metallurgical parameters;
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 of 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 titanium plate, then sending the raw material powder into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 20 mm;
502, adjusting the laser waveform to be a right trapezoid waveform according to the designed laser waveform and adjusting the slope of the right trapezoid waveform in the power attenuation stage
Figure BDA0002589706400000161
Corresponding to theta 26.6 deg. and according to designSetting the laser power P as 2300W, the laser action time T as 50s and the laser spot diameter D as 2.2mm as process parameters, and performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 501 by adopting laser to solidify the raw material powder at a set solidification rate after the raw material powder is melted to obtain a Ti-6Al-3Mo micro-area material; the radius r of the Ti-6Al-4V micro-area material is 0.8 mm.
FIG. 6 is an EDS scan of the Ti-6Al-3Mo micro-area material prepared in this example, FIG. 7a is a total distribution diagram of the contents of the elements in the Ti-6Al-3Mo micro-domain material prepared in this example, FIG. 7b is an EDS composition distribution diagram of Ti element content of Ti-6Al-3Mo micro-domain material prepared in this example, FIG. 7c is an EDS composition distribution diagram of Al element content of Ti-6Al-3Mo micro-domain material prepared in this example, FIG. 7d is an EDS composition distribution diagram of Mo element content of Ti-6Al-3Mo micro-area material prepared in this example, FIG. 8a is the EDS line scan macro topography of the Ti-6Al-3Mo micro-area material prepared in this example, FIG. 8b is a graph of EDS line scan data of Ti-6Al-3Mo micro-area material prepared in this example. As can be seen from FIGS. 6, 7a to 7d and 8a to 8b, the Ti, Al and Mo distribution in the Ti-6Al-3Mo domain material prepared in this example is uniform.
Example 6
The present embodiment is different from embodiment 4 only in that the laser power is adjusted to P10000W. FIG. 9 is a microstructure diagram of the Ti-6Al-3Mo micro-area material prepared in this example, and it can be seen from FIG. 9 that the Ti-6Al-3Mo micro-area material prepared in this example has uniform structure and high density, which indicates that the method of the present invention has good metallurgical effect on the novel alloy material.
The application of the crucible-free laser micro-area metallurgy method based on the laser light receiving path in the rapid verification of the computational materials is described in detail in the embodiment 7 to the embodiment 8.
Example 7
The embodiment comprises the following steps:
step one, mixing Ti-6Al-4V powder with the mass purity of 99.5% and the average particle size of 120 mu m and industrial pure B powder with the mass purity of 99.5% and the average particle size of 10 mu m according to the design components of Ti-6Al-4V-0.3B, adding 1% of PVA glue by mass percent for powder bonding and coating, ball-milling and mixing for 30min in a planetary ball mill, then placing in a vacuum drying furnace, drying for 8h under the conditions that the temperature is 70 ℃ and the vacuum degree is-0.07 MPa, and then obtaining 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, and obtaining a plurality of different laser micro-area metallurgical schemes which respectively comprise laser power, laser action time and laser light receiving paths, wherein the laser power P can be segmented into the following steps according to actual metallurgical conditions: low power range 100W ≦ P<2000W, medium power range 2000W ≤ P<6000W, wherein the high power range is 6000W or more and is not more than P and not more than 10000W; the laser action time T is segmented into: short time range of 3ms to T<30ms, and T is more than or equal to 3ms in the middle time range<T is more than or equal to 3s and less than or equal to 50s within a long time range of 3 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 in 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
Figure BDA0002589706400000181
Corresponding to 0<Theta is less than or equal to 30 degrees, or
Figure BDA0002589706400000182
Corresponding 30 °<Theta is less than or equal to 60 DEG, or
Figure BDA0002589706400000183
Corresponding 60 degree<θ<90 degrees; 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 speed and temperature gradient in the metallurgical process of each crucible-free laser micro-area by adopting a laser molten pool fixed-point temperature measurement method, investigating 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 rate 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, wherein the specific steps are as follows: (1) in a low power range, more metallurgical defects such as cracks, air holes and the like are easy to generate, and particularly, the refractory alloy micro-area material is adopted; in the medium power range, most micro-area materials have sufficient heat input, so that strong convection in a molten pool is realized, and micro-area materials with better metallurgical quality and good formability can be obtained according to reasonable combination; in a high power range, due to the great promotion of an input heat source, a better metallurgical effect can be obtained particularly for difficult/extremely refractory alloys; however, for most materials, too high a power can result in poor formability of the domain material in the medium power range; (2) micro-area metallurgy is carried out in a short time range, and metallurgical fusion defects exist in partial materials; micro-area metallurgy is carried out within a medium time range, and for most materials, micro-area materials with better metallurgical quality and formability can be obtained according to reasonable combination; the metallurgy effect of the material is obviously improved in a long-time range, but the metallurgy effect has a negative effect on the easily-cracked material; (3) in the laser light receiving path combination, the low-speed wave form range realizes the low-speed solidification of a molten pool, and the micro-area material is favorable for forming a structure consisting of a balance phase; the medium-speed wave form range realizes the medium-speed solidification of the molten pool, and the micro-area material forms a mixed structure consisting of a balanced phase and a non-balanced phase; the rapid waveform range realizes the rapid solidification of the molten pool, and is beneficial to the micro-area material to form a structure consisting of non-equilibrium phases; synthesizing the relationship between the laser micro-area metallurgical parameters and the micro-area materials, selecting the corresponding laser waveform according to the solidification characteristics of the target product, and combining different metallurgical parameters by adjusting different solidification conditions to obtain the micro-area materials with different tissues and properties;
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 of 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 titanium plate, then sending the horizontal titanium plate into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 2 mm;
step 502, adjusting the laser waveform to be a right trapezoid waveform according to the designed laser waveform, setting the slope k of the right trapezoid waveform at the power attenuation stage to be 3, setting the corresponding theta to be 72 degrees, setting the laser power P to be 4000W according to the designed process parameters, setting the laser action time T to be 20ms, setting the laser spot diameter D to be 2.2mm, and performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 501 by adopting laser to solidify the raw material powder according to the set solidification rate after melting to obtain a Ti-6Al-4V-0.3B micro-area material 1; the radius r of the Ti-6Al-4V-0.3B1 micro-area material is 0.8 mm.
Step six, observing and detecting the microstructure and the microhardness of the Ti-6Al-4V-0.3B micro-area material 1 prepared in the step five, then comparing the observed detection result with the simulation result of the computer material science on Ti-6Al-4V-0.3B to verify that the observed detection result and the simulation result of the computer material science on Ti-6Al-4V-0.3B have partial difference, adjusting the laser power P in the laser micro-area metallurgical parameters designed in the step five to 1000W to prepare the Ti-6Al-4V-0.3B micro-area material 2, and repeating the preparation process, the observation detection process and the comparison and verification process in sequence to find that the observed detection result is basically consistent with the simulation result of the computer material science on Ti-6Al-4V-0.3B after the laser micro-area metallurgical parameters are adjusted, wherein the specific process flow of the embodiment is shown in figure 10.
FIG. 11a is a microstructure diagram of the Ti-6Al-4V-0.3B micro-domain material 1 prepared in this example, and FIG. 11B is a microstructure diagram of the Ti-6Al-4V-0.3B micro-domain material 2 prepared in this example, and it can be seen from FIG. 11a and FIG. 11B that the microstructure morphology and the grain size of the Ti-6Al-4V-0.3B micro-domain materials prepared under different metallurgical parameters are significantly different.
The microhardness and volume fraction of TiB in the microstructure of the Ti-6Al-4V-0.3B domain material 1 (i.e., material 1) and the Ti-6Al-4V-0.3B domain material 2 (i.e., material 2) prepared in this example were measured and compared with the simulation results of the computational materials science, and the results are shown in table 1 below.
TABLE 1
Figure BDA0002589706400000201
As can be seen from Table 1, the method of the present invention affects the microstructure by adjusting the metallurgical parameters of the laser microcell to improve the actual properties of the material, and the comparison with the simulation results of computational materials shows that the properties of the microcell material prepared by the method of the present invention are basically close to the simulation results and have the same change rule, and the coincidence of the simulation results and the actual experiment results can be realized by the metallurgical parameters of the laser microcell, which indicates that the method of the present invention meets the rapid verification requirements of computational materials.
Example 8
The embodiment comprises the following steps:
step one, mixing Ti-6Al-4V powder with the mass purity of 99.5% and the average particle size of 120 microns and industrial pure B powder with the mass purity of 99.5% and the average particle size of 10 microns according to the design components of Ti-6Al-4V-0.5B, adding 1% of PVA glue by mass percentage for bonding and coating, ball-milling and mixing for 30min in a planetary ball mill, then placing in a vacuum drying furnace, drying for 8h under the conditions that the temperature is 80 ℃ and the vacuum degree is-0.07 MPa, and then obtaining 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, and obtaining a plurality of different laser micro-area metallurgical schemes which respectively comprise laser power, laser action time and laser light receiving paths, wherein the laser power P can be segmented into the following steps according to actual metallurgical conditions: low power range 100W ≦ P<2000W, medium power range 2000W ≤ P<6000W, high power range 6000W less than or equal toP is less than or equal to 10000W; the laser action time T is segmented into: short time range of 3ms to T<30ms, and T is more than or equal to 3ms in the middle time range<T is more than or equal to 3s and less than or equal to 50s within a long time range of 3 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 in 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
Figure BDA0002589706400000211
Corresponding to 0<Theta is less than or equal to 30 DEG, or
Figure BDA0002589706400000212
Corresponding 30 °<Theta is less than or equal to 60 DEG, or
Figure BDA0002589706400000213
Corresponding 60 degree<θ<90 degrees; 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 speed and temperature gradient in the metallurgical process of each crucible-free laser micro-area by adopting a laser molten pool fixed-point temperature measurement method, investigating 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 rate 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, wherein the specific steps are as follows: (1) in a low power range, more metallurgical defects such as cracks, air holes and the like are easy to generate, and particularly, the refractory alloy micro-area material is adopted; in the medium power range, most micro-area materials have sufficient heat input, so that strong convection in a molten pool is realized, and micro-area materials with better metallurgical quality and good formability can be obtained according to reasonable combination; in a high power range, due to the great improvement of an input heat source, a better metallurgical effect can be obtained especially for difficult/extremely refractory alloys; however, for most materials, too high a power can result in poor formability of the domain material compared to the medium power range; (2) micro-area metallurgy is carried out in a short time range, and metallurgical fusion defects exist in partial materials; micro-area metallurgy is carried out within a medium time range, and for most materials, micro-area materials with better metallurgical quality and formability can be obtained according to reasonable combination; the metallurgy effect of the material is obviously improved in a long-time range, but the metallurgy effect has a negative effect on the easily-cracked material; (3) in the laser light receiving path combination, the low-speed wave form range realizes the low-speed solidification of a molten pool, and the micro-area material is favorable for forming a structure consisting of a balance phase; the medium-speed wave form range realizes the medium-speed solidification of the molten pool, and the micro-area material forms a mixed structure consisting of a balanced phase and a non-balanced phase; the rapid waveform range realizes the rapid solidification of the molten pool, and is beneficial to forming a structure consisting of non-equilibrium phases by the micro-area material; synthesizing the relationship between the laser micro-area metallurgical parameters and the micro-area materials, selecting the corresponding laser waveform according to the solidification characteristics of the target product, and combining different metallurgical parameters by adjusting different solidification conditions to obtain the micro-area materials with different tissues and properties;
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 of 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, paving raw material powder on a horizontal titanium plate in a powder bed mode, then sending the raw material powder into a laser working vacuum box of laser micro-area metallurgical equipment, introducing high-purity Ar gas into the laser working vacuum box, and controlling the oxygen content in the laser working vacuum box to be not more than 100 ppm; the thickness of the paving is 2 mm;
step 502, adjusting the laser waveform to be a right trapezoid waveform according to the designed laser waveform, setting the slope k of the right trapezoid waveform at the power attenuation stage to be 3, setting the corresponding theta to be 72 degrees, setting the laser power P to be 3000W according to the designed process parameters, setting the laser action time T to be 20ms, setting the laser spot diameter D to be 2.2mm, and performing laser micro-area fixed-point melting on the raw material powder laid on the horizontal titanium plate in the step 501 by adopting laser to solidify the raw material powder at a set solidification rate after melting to obtain a Ti-6Al-4V-0.5B micro-area material; the radius r of the Ti-6Al-4V-0.5B micro-area material is 0.8 mm;
and sixthly, observing and detecting the microstructure and the microhardness of the Ti-6Al-4V-0.5B micro-area material prepared in the fifth step, and then comparing the observation and detection result with the simulation result of Ti-6Al-4V-0.5B in computer materials science to verify that the two are basically consistent.
FIG. 12 is a microstructure diagram of the Ti-6Al-4V-0.5B domain material prepared in this example, and from a comparison of FIG. 12 with FIGS. 11a and 11B, the second phase precipitates and the structure of the Ti-6Al-4V-0.5B domain material prepared in this example with the addition of boron are significantly different from those of the Ti-6Al-4V-0.3B domain material prepared in example 7.
The microhardness and volume fraction of TiB in the microstructure of the Ti-6Al-4V-0.5B domain material (i.e., material 1) prepared in this example were measured and compared to the simulation results of computational materials science, and the results are shown in table 2 below.
TABLE 2
Figure BDA0002589706400000231
As can be seen from Table 2, the properties of the domain material prepared by the method of the present invention substantially match the simulation results, which shows that the method of the present invention meets the requirement of rapid verification of computational materials science.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.

Claims (5)

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 laying thickness is 2 mm-20 mm;
step 502, setting laser power and laser action time, and simultaneously passingAdjusting the laser waveform to set solidification parameters, and then performing 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 parameters after being melted to obtain a micro-area material; the laser power is 100W-10000W, the laser action time is 5 ms-50 s, the laser waveform is a rectangular waveform or a right-angle trapezoidal waveform, the right-angle trapezoidal waveform comprises a peak power continuous stage and a power attenuation stage of the laser, and the right-angle trapezoidal waveform in the power attenuation stage is along with the slope of an oblique sidekAnd bevel angle θ adjustment, whereink= tan θ, slopekHas a value range of
Figure 753155DEST_PATH_IMAGE002
Corresponding to 0<Theta is less than or equal to 30 DEG, or
Figure 670295DEST_PATH_IMAGE004
Corresponding to 30 °<Theta is less than or equal to 60 DEG, or
Figure 117398DEST_PATH_IMAGE008
Corresponding to 60 °<θ<90°。
2. The crucible-free laser micro-area metallurgy method based on laser beam receiving path regulation and control as claimed in 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 equipment used for drying treatment in the step one is a vacuum drying furnace, the temperature of the drying treatment is 70-125 ℃, the time is 2-8 h, and the vacuum degree is-0.05 MPa-0.085 MPa.
5. The application of the crucible-free laser micro-area metallurgy method based on laser collection path regulation and control as claimed in any one of claims 1 to 4 in the rapid verification of computational materials science is characterized in that the application comprises the following specific processes: firstly, setting a laser light receiving path by adjusting the laser waveform in laser microcell metallurgical equipment according to the solidification condition designed by computational materials science for a material to be researched to ensure that the solidification condition is consistent, obtaining laser microcell metallurgical parameters, then preparing the material to be microcell by a crucible-free laser microcell metallurgical method, measuring the tissue and performance parameters of the microcell material, 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, feeding back and adjusting the laser microcell 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 microcell material are consistent with the simulation result of the computational materials science.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019029031A1 (en) * 2017-08-07 2019-02-14 华南理工大学 Additive manufacturing method for lead-free environmentally-friendly high-strength brass alloy
CN109746446A (en) * 2019-03-18 2019-05-14 长安大学 A kind of method for building up of the material gene pool based on laser microcell metallurgy
CN209614253U (en) * 2019-03-18 2019-11-12 长安大学 A kind of laser microcell metallurgical plant

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190389002A1 (en) * 2018-03-27 2019-12-26 Xiao-Dong Xiang Micro-zone laser heating apparatus and method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019029031A1 (en) * 2017-08-07 2019-02-14 华南理工大学 Additive manufacturing method for lead-free environmentally-friendly high-strength brass alloy
CN109746446A (en) * 2019-03-18 2019-05-14 长安大学 A kind of method for building up of the material gene pool based on laser microcell metallurgy
CN209614253U (en) * 2019-03-18 2019-11-12 长安大学 A kind of laser microcell metallurgical plant

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
激光快速修复Ti-6Al-4V合金的显微组织与力学性能;薛蕾等;《稀有金属材料与工程》;20070615(第06期);全文 *
激光熔覆纳米Al_2O_3的粉末冶金件的表面组织;刘燕等;《吉林大学学报(工学版)》;20040730(第03期);全文 *
薛蕾等.激光快速修复Ti-6Al-4V合金的显微组织与力学性能.《稀有金属材料与工程》.2007,(第06期), *

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