CN-121988754-A - Method and equipment for inhibiting reinforced particle loss in laser additive manufacturing of metal matrix composite

CN121988754ACN 121988754 ACN121988754 ACN 121988754ACN-121988754-A

Abstract

The invention relates to a method and equipment for inhibiting reinforced particle loss in laser additive manufacturing of a metal matrix composite, which comprises the steps of establishing a three-dimensional model of the metal matrix composite, carrying out layering slicing treatment on the metal matrix composite, determining technological parameters of annular continuous laser and pulse laser, putting metal matrix composite powder into a powder bin, introducing argon for protection, carrying out laser additive manufacturing according to the determined technological parameters, acquiring a splashing duty ratio in real time, and controlling a laser scanning system to generate corresponding laser according to the splashing duty ratio to finish manufacturing of the metal matrix composite. According to the invention, by the synergistic effect of the double-beam paraxial laser, the annular continuous laser is utilized to provide a more stable thermal field compared with Gaussian continuous laser to realize the melting of matrix powder, and the dissolution loss of reinforced particles is effectively reduced by controlling process parameters.

Inventors

HAN QUANQUAN
ZHAO PENG
WANG LIQIAO
ZHANG ZHENHUA
LIU GUOJIE
ZHU MIN
ZHANG SHAOYU

Assignees

山东大学

Dates

Publication Date: 20260508
Application Date: 20260409

Claims (9)

1. A method of suppressing the loss of reinforcing particles in a laser additive manufactured metal matrix composite, comprising: Step 1, establishing a three-dimensional model of a metal matrix composite material, and carrying out layering slicing treatment; Step 2, determining technological parameters of laser according to the reinforced particles, putting metal matrix composite powder into a powder bin, and introducing argon for protection; And 3, performing laser additive manufacturing according to the determined technological parameters, acquiring the splashing duty ratio in real time, and controlling a laser scanning system to generate corresponding laser according to the splashing duty ratio to finish manufacturing the metal matrix composite.
2. The method of suppressing the loss of reinforcing particles in a metal matrix composite produced by laser additive manufacturing according to claim 1, wherein the specific implementation of step 1 comprises: Establishing a three-dimensional model of the metal matrix composite to be formed, importing the three-dimensional model into slicing software, and confirming the space position of the metal matrix composite to be formed in a forming bin; Setting a powder spreading layer thickness S=D L , wherein D L is the depth of a molten pool, carrying out layering slicing treatment on a three-dimensional model of the metal matrix composite material to be formed after the position is determined according to the preset powder spreading layer thickness, and extracting the two-dimensional section profile of each layer, wherein the slicing thickness of each layer is the powder spreading layer thickness.
3. A method of suppressing loss of reinforcing particles in a laser additive manufactured metal matrix composite according to claim 2, wherein determining process parameters of the laser from the reinforcing particles in step 2 comprises: the technological parameters of the laser include laser power P, scanning interval H, scanning speed V and scanning strategy; The laser power P is set as P L ＜P＜P P , wherein P L is the minimum laser power of the matrix material which can reach the liquid phase temperature, and P P is the minimum laser power of the reinforced particles which can reach the melting temperature; The scanning interval H is set to W L/2 ＜H＜W L , wherein W L is the width of a molten pool, and W L/2 is one half of the width of the molten pool; The scanning speed V is set to v=v M , wherein V M is the maximum laser scanning speed at which the metal matrix composite material does not generate unmelted defects; The scanning strategy is that the laser scanning direction is parallel to the longest edge of each layer in the layered slice of the metal matrix composite.
4. A method of suppressing the loss of reinforcing particles in a metal matrix composite produced by laser additive manufacturing according to claim 3, wherein the step 2 of placing the metal matrix composite powder into a powder bin and introducing argon gas for protection comprises: Putting metal matrix composite powder into a powder bin, wherein the metal matrix composite powder specifically comprises a GH3536 matrix material and 5wt.% TiC reinforced particles, and the GH3536 matrix material comprises, by mass, 0.06% of C, 21.5% of Cr, 1.6% of Co, 0.6% of W, 8.5% of Mo, 0.09% of Al, 0.05% of Ti, 18.9% of Fe, less than or equal to 0.01% of B, 0.1% of Si, 0.25% of Mn, and the balance of Ni and other unavoidable impurities; And (3) adopting a single-side gas flow mode, and leading high-purity argon into the forming bin in the direction perpendicular to the laser scanning direction until the oxygen volume fraction in the forming bin is reduced to below 500 ppm.
5. The method of suppressing the loss of reinforcing particles in a metal matrix composite produced by laser additive manufacturing according to claim 4, wherein the specific implementation of step 3 comprises: Performing laser additive manufacturing on the metal matrix composite according to the determined technological parameters and the slice thickness of each layer of slice, collecting images in a forming bin in real time, performing threshold segmentation processing on the collected images, namely converting the images into gray images, then introducing a specific gray threshold, judging pixels with gray values lower than the threshold as suspected splash characteristic pixels and assigning the pixels as 1, otherwise, assigning the pixels as 0; Performing morphological feature analysis on the suspected splash feature pixels with the value of 1, namely extracting roundness parameters of the suspected splash feature pixels Comparing the roundness parameter with a preset roundness threshold value, and judging the suspected splash characteristic pixel as splash characteristic if the roundness parameter is larger than the roundness threshold value; Calculating a splash duty ratio, namely counting the total number of pixels judged to be splash features in a preset surrounding area of the metal matrix composite material, and dividing the total number of pixels in the surrounding area of the metal matrix composite material by the total number of pixels to obtain the splash duty ratio; if the calculated splashing ratio is higher than the threshold value, controlling a laser scanning system to generate double-beam paraxial laser according to preset technological parameters, scanning a slicing area of the metal matrix composite material, and completing manufacturing of the metal matrix composite material, wherein the double-beam paraxial laser comprises annular continuous laser emitted by a continuous laser and pulse laser emitted by a pulse laser; Otherwise, only generating annular continuous laser with preset technological parameters to finish the manufacture of the metal matrix composite; Simultaneously, continuously introducing argon in the manufacturing process, wherein the flow speed of the argon is controlled to be 1-3 m/s until the metal matrix composite is formed and cooled to room temperature; the diameter of the light spot of the pulse laser is equal to that of the annular continuous laser, the diameter of the light spot is 150-170 mu m, the light spot is closely attached, the pulse width of the pulse laser is 10-100 ns, and the technological parameters of the pulse laser are consistent with those of the annular continuous laser.
6. The device for inhibiting the loss of reinforced particles in the metal matrix composite manufactured by the laser additive, which is used for realizing the method for inhibiting the loss of reinforced particles in the metal matrix composite manufactured by the laser additive according to claim 5, is characterized by comprising a forming bin, an atmosphere system, a laser scanning system and an on-line monitoring system, wherein the forming bin, the atmosphere system, the laser scanning system and the on-line monitoring system are all connected with a processing platform; An atmosphere system is arranged at the lower side of the laser scanning system, and a forming bin is arranged at the lower side of the atmosphere system; One side of the laser scanning system is provided with an on-line monitoring system.
7. An apparatus for suppressing the loss of reinforcing particles in a laser additive manufactured metal matrix composite according to claim 6, wherein the forming bin comprises a powder bin, a doctor blade, and a substrate; the online monitoring system comprises a high-speed camera; a base plate is arranged on one side of the powder bin; A scraper is arranged on the upper side of the powder bin.
8. An apparatus for suppressing the loss of enhanced particles in a laser additive manufactured metal matrix composite according to claim 7, wherein the laser scanning system comprises a pulsed laser device and a continuous laser device; a continuous laser device is arranged at the lower side of the pulse laser device; the pulse laser device comprises a pulse laser, a first optical path system, a first galvanometer system and an F-theta lens which are sequentially arranged along an optical path; the continuous laser device comprises a continuous laser, a second optical path system, a second galvanometer system and an F-theta lens which are sequentially arranged along an optical path; The pulsed laser device and the continuous laser device share the same F-theta lens.
9. The apparatus for suppressing the loss of particles in a metal matrix composite produced by laser additive manufacturing of claim 8, wherein the first optical path system and the second optical path system comprise a collimator lens, a beam expander lens, a half-wave plate and a thin film polarizer arranged in sequence along the optical path; the laser beams emitted by the pulse laser and the continuous laser sequentially pass through the collimating lens, the beam expander, the half-wave plate and the thin film polarizer, wherein the half-wave plate is arranged at the front end of the thin film polarizer, and the continuous stepless adjustment of the transmitted laser power is realized by matching with the thin film polarizer.

Description

Method and equipment for inhibiting reinforced particle loss in laser additive manufacturing of metal matrix composite Technical Field The invention relates to a method and equipment for inhibiting reinforced particle loss in laser additive manufacturing of a metal matrix composite material, and belongs to the technical field of additive manufacturing. Background The metal matrix composite is a combination of a reinforcing material (TiC, Y 2O3、TiB2 and the like) and a metal or alloy matrix material (GH 3536, TC4, al7075 and the like), wherein the nickel matrix composite has excellent high-temperature mechanical property and corrosion resistance and is applied to an aerospace hot end component. Laser Powder Bed Fusion (LPBF) is one of the most widely used techniques in laser additive manufacturing that utilizes a focused high-energy laser beam to melt powder layer by layer to produce three-dimensional complex-shaped metal parts with relatively strong metallurgical bonds. The LPBF technique ensures efficient integration and uniform dispersion of reinforcing particles in the metal matrix composite compared to conventional manufacturing methods. Taking submicron Y 2O3 particle reinforced nickel-based composite (GRX 810) as an example, the ultimate service temperature of LPBF formed test specimens reaches 1093 ℃, and the test specimens have been successfully applied to rocket engine parts of a certain model. The traditional LPBF equipment mainly adopts Gaussian laser as an energy source, and intensive researches find that under the action of Gaussian continuous laser with high power density, reinforced particles in the metal matrix composite material undergo complex trans-scale dynamic evolution, so that more than 30wt.% of reinforced particles are lost, a large amount of slag and splashes are formed, and the surface quality of a formed sample and the strengthening effects of particle pinning, bearing and the like are seriously weakened. In the aspect of molten pool regulation, the invention patent of publication No. CN114871451A discloses a high-formability aluminum alloy material based on laser beam shaping and a preparation method thereof, and the proposal shows that a shaped beam (flat top, annular continuous laser) can stabilize the turbulence of a laser molten pool and reduce the thermal gradient. The invention patent of publication No. CN116140807A discloses an additive manufacturing and welding method based on low-heat input pulse laser shock waves, which regulates and controls the flow of a molten pool and overcomes the constraint of surface tension by pulse laser shock force and can reduce the coupling effect caused by heat input. However, although these methods can regulate the stability of the molten pool, it is still difficult to suppress the loss of reinforcing particles during the laser additive manufacturing process of the metal matrix composite, thereby affecting the high quality preparation of the metal matrix composite. In summary, there is still a lack of effective means for suppressing the loss of reinforced particles in the manufacture of metal matrix composite materials by laser additive, and in order to break through the service temperature limit of the particle reinforced nickel matrix composite materials in the key fields of aerospace and the like, it is highly desirable to invent a method and an apparatus for suppressing the loss of reinforced particles in the manufacture of metal matrix composite materials by laser additive. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a method and equipment for inhibiting the loss of reinforced particles in the laser additive manufacturing metal matrix composite, which introduces a double-beam paraxial laser strategy, utilizes annular continuous laser to provide a pure thermal field to stably melt the metal matrix composite, simultaneously utilizes pulse laser to apply a force field in the gravity direction, determines the technological parameters of the laser according to reinforced particles, monitors the loss and splashing condition of the particles in real time, controls the start and stop of the laser, and realizes the effective inhibition of the dissolution loss and the splashing loss of the reinforced particles in the LPBF formed metal matrix composite, thereby improving the mechanical property of the composite. The technical scheme of the invention is as follows: A method of inhibiting loss of reinforcing particles in a laser additive manufactured metal matrix composite, comprising: Step 1, establishing a three-dimensional model of a metal matrix composite material, and carrying out layering slicing treatment; Step 2, determining technological parameters of laser according to the reinforced particles, putting metal matrix composite powder into a powder bin, and introducing argon for protection; And 3, performing laser additive manufacturing according to the determined technological parameters, acquiri