Preparation method of high-toughness metal ceramic composite material component for selective laser melting

Abstract

The invention relates to the technical field of additive manufacturing, in particular to a preparation method of a high-toughness metal ceramic composite component for selective laser melting. The method comprises the following steps: preparing spherical powder from Co, Cr, TaC, VC and WC raw materials in preset weight percentages through inert gas atomization; determining a first comprehensive mass index based on the fluidity and particle size distribution data of the powder to dynamically select the screening strength; determining a second comprehensive quality index based on fluidity, particle size distribution and sphericity degree data of the screened powder so as to adaptively select a forming strategy of selective laser melting forming, degreasing sintering or intensified sintering; a transition layer is formed by adopting a cold spraying process, and the quality of the transition layer is ensured through real-time quality evaluation and a multi-stage parameter compensation strategy. Through dynamic adjustment and compensation of the whole process, the problems of unstable powder quality, single forming process and weak interface bonding force are systematically solved, and waste-free efficient preparation of high-toughness and high-reliability components is achieved.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and in particular to a method for preparing high-toughness metal-ceramic composite material components for selective laser melting. Background Technology

[0002] Selective laser melting (SLM) is an additive manufacturing technology widely used in the forming of metal-ceramic composite components. Chinese Invention Patent Publication No. CN114472898A discloses a gradient metal-ceramic coating prepared by selective laser sintering and its preparation method. The gradient metal-ceramic coating consists of an underlayer, a transition layer, and an outer layer; the underlayer is a high corrosion-resistant nickel-based high corrosion-resistant alloy metal layer, and its composition is as follows: The outer layer is a ceramic layer with the following composition: C 12.5-18.7%, N 19.7-23.4%, B 15.8%, Re 2.7%, and the remainder being Si; the transition layer is a metal-ceramic composite layer; the coating is sintered using selective laser sintering (SLS). This invention uses SLS to form a ceramic-metal composite coating with metallurgical bonding and essentially continuous changes in physical and mechanical properties, avoiding ceramic layer detachment caused by interlayer stress concentration. This effectively improves the high-temperature resistance, oxidation resistance, and corrosion resistance of the ceramic coating, making it suitable for mass production. However, the following problems still exist: The powder quality of metal-ceramic composites is often unstable, such as poor flowability, uneven particle size distribution, and low sphericity, which makes it easy for splashing, pores and cracks to occur during the molding process. The molding process is limited and cannot be adapted to the powder quality, resulting in a low yield. At the same time, the interfacial bonding between the metal-ceramic matrix and the functional coating is weak, affecting the reliability of the components during service.

[0003] Therefore, there is an urgent need in this field for a preparation method that can systematically solve the above problems, so as to achieve precise control of powder quality, and to dynamically and adaptively select or even compensate for and optimize the molding process based on powder quality, while enhancing interfacial bonding and quality consistency, thereby fundamentally breaking through the technical bottleneck of low yield and poor reliability of high-toughness metal-ceramic composite materials in laser selective melting applications. Summary of the Invention

[0004] Therefore, the present invention provides a method for preparing high-toughness metal-ceramic composite material components for laser selective melting, in order to overcome the problems of unstable powder quality, simple molding process, weak interfacial bonding and poor quality consistency in the prior art.

[0005] To achieve the above objectives, the present invention provides a method for preparing high-toughness metal-ceramic composite material components for laser selective melting, comprising the following steps: Step S1: Using a preset weight percentage of Co, Cr, TaC, VC and the remaining weight percentage of WC as raw materials, spherical powder is prepared by atomization with inert gas. Step S2: Based on the first flowability data and the first particle size distribution data of the spherical powder, determine the first comprehensive quality index of the spherical powder to determine the sieving treatment level, and perform sieving treatment on the spherical powder using the sieving treatment parameters corresponding to the sieving treatment level, wherein the sieving treatment level includes standard sieving, medium-strength sieving, and high-strength sieving. Step S3: Based on the second flowability data, second particle size distribution data, and sphericity data of the spherical powder after sieving, determine the flowability score, particle size distribution score, and sphericity score respectively to determine the second comprehensive quality index. Step S4: Determine the spherical powder usage strategy based on the second comprehensive quality index to obtain SLM molded parts, wherein the spherical powder usage strategy includes selective laser melting molding and sintering molding after debinding; Step S5: Using a cold spraying process, Ni-Co-Cr-Al-Y series alloy powder is sprayed onto the substrate surface to form a transition layer; Step S6: Determine the third comprehensive quality index based on the porosity and bonding strength of the transition layer during the cold spraying process; Step S7: Based on the third comprehensive quality index, the passability of the transition layer is evaluated in real time. If the transition layer is found to be unqualified, a transition layer compensation strategy is determined to be implemented until the transition layer is qualified. Then, the cold spraying process is stopped to complete the preparation. The compensation strategy includes a primary parameter adjustment strategy based on the relative deviation between the porosity of the transition layer and the bonding strength of the interface, which determines the adjustment of the gas temperature or spraying distance, and a secondary parameter adjustment strategy that simultaneously adjusts the gas temperature, pressure and spraying distance.

[0006] Further, in step S1, the process of preparing spherical powder by atomization with inert gas includes: Step S11: Weigh out 5%–15% Co, 3%–10% Cr, 1%–5% TaC, 0.5%–3% VC, and the remaining weight percentage of WC according to the weight percentage to obtain mixed raw materials; Step S12: The mixed raw materials are put into a vacuum induction melting furnace and heated to a molten state under inert gas protection to obtain an alloy melt; Step S13: The alloy melt is atomized using the inert gas to obtain the spherical powder.

[0007] Further, in step S2, the process of determining the first comprehensive quality index includes: Step S21: Characterize the first flowability data based on the flow time of the spherical powder; Step S22: Determine the first particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder; Step S23: The weighted sum of the flow time and the particle size distribution data is determined as the first comprehensive quality index.

[0008] Further, in step S2, the process of determining the screening treatment level includes: The first comprehensive quality index is compared and analyzed with the first preset comprehensive quality index; Based on the result that the first comprehensive quality index is greater than or equal to the first threshold in the first preset comprehensive quality index, the screening process level is determined to be standard screening. Alternatively, based on the result that the first comprehensive quality index is less than the first threshold in the first preset comprehensive quality index and is greater than or equal to the second threshold in the first preset comprehensive quality index, the screening treatment level is determined to be medium-intensity screening. Alternatively, based on the result that the first comprehensive quality index is less than the second threshold in the first preset comprehensive quality index, the screening process level is determined to be high-intensity screening; Wherein, the first threshold in the first preset comprehensive quality index is greater than the second threshold in the first preset comprehensive quality index.

[0009] Furthermore, the process of sieving the powder includes: Step S251: Place the spherical powder into an ultrasonic vibrating sieve. Step S252: Set the sieve aperture to 15μm-45μm, and use the combined action of mechanical vibration and ultrasonic oscillation to make the spherical powder pass through the sieve. Step S253: Collect the powder that passes through the sieve as qualified powder.

[0010] Further, in step S3, the process of determining the second comprehensive quality index includes: Step S31: Determine the correction angle of the spherical powder after sieving based on the flow rate value of the spherical powder after sieving, and characterize the second flowability data; Step S32: Determine the second particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder after sieving. Step S33: Determine the sphericity data based on the image of the spherical powder after sieving; Step S34: Compare and analyze the second flowability data, the second particle size distribution data, and the sphericity data with the corresponding preset threshold ranges, and determine the flowability score, the particle size distribution score, and the sphericity score based on the normalization results of the comparison and analysis results. Step S35: The weighted sum of the flowability score, the particle size distribution score, and the sphericity score is determined as the second comprehensive quality index.

[0011] Further, in step S4, the process of determining the spherical powder usage strategy based on the second comprehensive quality index includes: The second comprehensive quality index is compared and analyzed with the second preset comprehensive quality index; Based on the result that the second comprehensive quality index is greater than or equal to the second threshold in the second preset comprehensive quality index, the selected area laser melting forming strategy is determined. Alternatively, based on the result that the second comprehensive quality index is greater than or equal to the first threshold of the second preset comprehensive quality index and less than the second threshold of the second preset comprehensive quality index, the strategy of degreasing and then sintering is determined. Alternatively, based on the result that the second comprehensive quality index is less than the first threshold in the second preset comprehensive quality index, it is determined that the current batch of spherical powder is not suitable for molding, and the process returns to step S1.

[0012] Furthermore, in step S5, the gas used in the cold spraying process is nitrogen, and the gas temperature is controlled within the range of 400℃ to 600℃, the gas pressure within the range of 3MPa to 5MPa, and the spraying distance within the range of 15mm to 25mm.

[0013] Further, in step S6, the process of determining the third comprehensive quality index includes: Step S61: Determine the porosity of the transition layer based on the microscopic image of the transition layer; Step S62: Determine the bonding strength based on the bonding strength between the transition layer and the substrate; Step S63: Construct a mathematical model based on the porosity and the bonding surface strength to calculate the third comprehensive quality index, wherein the porosity is negatively correlated with the third comprehensive quality index and the bonding surface strength is positively correlated with the third comprehensive quality index.

[0014] Furthermore, in step S7, the process of determining the transition layer compensation strategy includes: The third comprehensive quality index is compared and analyzed with the third preset comprehensive quality index in real time. Based on the result that the third comprehensive quality index is greater than or equal to the third preset comprehensive quality index, the first-level parameter adjustment strategy is determined to be adopted. Alternatively, based on the result that the third comprehensive quality index is less than the third preset comprehensive quality index, the secondary parameter adjustment strategy is determined to be adopted.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: At the material and powder source level, by adopting a specific component system of Co-Cr-TaC-VC-WC and using inert gas atomization to prepare spherical powder, the high chemical purity, high sphericity and low porosity of the powder are ensured from the source. The introduction of TaC and VC effectively suppressed the abnormal growth of WC grains and improved the toughness of the matrix, laying the material foundation for the preparation of highly dense and tough components.

[0016] Furthermore, at the level of powder quality control and decision-making, by introducing a first comprehensive quality index to screen and classify the raw powder, an objective powder batch access standard was established, effectively preventing unqualified powder from entering subsequent processes.

[0017] Furthermore, by introducing sphericity and constructing a second comprehensive quality index, precise evaluation and resource optimization of the sieved powder are achieved. This enables adaptive selection of selective laser melting or debinding sintering strategies, thereby maximizing the utilization rate of high-quality powder and the overall yield while ensuring component performance.

[0018] Furthermore, at the level of interface bonding and reinforcement, a Ni-Co-Cr-Al-Y alloy transition layer is deposited on the substrate formed by SLM using a low-temperature cold spraying process. This cleverly utilizes the solid-state deposition characteristics to avoid the thermal impact of high temperature on the substrate, while achieving a strong metallurgical bond between the transition layer and the substrate. This provides an ideal substrate for subsequent functional coatings and significantly improves the interface bonding and service reliability of the component.

[0019] Furthermore, at the level of closed-loop quality control throughout the entire process, by real-time detection of the porosity and bonding strength of the transition layer and calculation of the third comprehensive quality index, a parameter compensation strategy is triggered, establishing an intelligent closed-loop quality control loop for real-time prevention and control. This ensures the stable and reliable quality of the transition layer of each produced component, systematically solving the problem of quality consistency.

[0020] Furthermore, by integrating multiple manufacturing processes into an organic and intelligently responsive system, the core technical challenges faced by metal-ceramic composite materials in laser selective melting, such as unstable powder quality, single molding process, weak interfacial bonding, and poor quality consistency, have been systematically overcome. Ultimately, this has enabled the efficient, high-yield, and waste-free preparation of high-toughness, high-reliability components. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the steps of a method for preparing high-toughness metal-ceramic composite material components using laser selective melting, as described in an embodiment of the present invention. Figure 2 This is a flowchart illustrating the steps involved in preparing spherical powder using inert gas atomization, as described in an embodiment of the present invention. Figure 3 A flowchart illustrating the steps for determining the first comprehensive quality index in an embodiment of the present invention; Figure 4 A flowchart illustrating the steps for determining the second comprehensive quality index in an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0023] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0024] The first, second, and third comprehensive quality indices of this invention are dimensionless values ​​calculated using a mathematical model based on multiple process performance indicators. These indices are used for quantitative evaluation and decision-making regarding powder quality or coating quality. The specific calculation methods are illustrated below through examples, but the scope of protection of this invention is not limited thereto.

[0025] Please see Figure 1 As shown, Figure 1 This is a flowchart illustrating the steps of a method for preparing high-toughness metal-ceramic composite material components using laser selective melting, as described in an embodiment of the present invention.

[0026] This embodiment describes a method for preparing high-toughness metal-ceramic composite material components for laser selective melting, comprising the following steps: Step S1: Using a preset weight percentage of Co, Cr, TaC, VC and the remaining weight percentage of WC as raw materials, spherical powder is prepared by atomization with inert gas. Step S2: Based on the first flowability data and the first particle size distribution data of the spherical powder, determine the first comprehensive quality index of the spherical powder to determine the sieving treatment level, and perform sieving treatment on the spherical powder using the sieving treatment parameters corresponding to the sieving treatment level. The sieving treatment level includes standard sieving, medium-strength sieving, and high-strength sieving. Step S3: Based on the second flowability data, second particle size distribution data, and sphericity data of the spherical powder after sieving, determine the flowability score, particle size distribution score, and sphericity score respectively to determine the second comprehensive quality index. Step S4: Determine the spherical powder application strategy based on the second comprehensive quality index to obtain SLM molded parts. The spherical powder application strategy includes selective laser melting and sintering after debinding. Step S5: Using a cold spraying process, Ni-Co-Cr-Al-Y series alloy powder is sprayed onto the substrate surface to form a transition layer; Step S6: Determine the third comprehensive quality index based on the porosity of the transition layer and the bonding strength during the cold spraying process. Step S7: The passability of the transition layer is evaluated in real time based on the third comprehensive quality index. If the transition layer is unqualified, a transition layer compensation strategy is determined. The process continues until the transition layer is qualified. Then, the cold spraying process is stopped to complete the preparation. The compensation strategy includes a primary parameter adjustment strategy based on the relative deviation between the porosity of the transition layer and the bonding strength of the interface, which adjusts the gas temperature or spraying distance. The secondary parameter adjustment strategy simultaneously adjusts the gas temperature, pressure and spraying distance.

[0027] Please see Figure 2 As shown, Figure 2 This is a flowchart illustrating the steps involved in preparing spherical powder using inert gas atomization, as described in an embodiment of the present invention.

[0028] Specifically, in step S1, the process of preparing spherical powder by atomization with inert gas includes: Step S11: Weigh out 5%–15% Co, 3%–10% Cr, 1%–5% TaC, 0.5%–3% VC, and the remaining weight percentage of WC according to the weight percentage to obtain mixed raw materials; Step S12: The mixed raw materials are put into a vacuum induction melting furnace and heated to a molten state under the protection of inert gas to obtain an alloy melt; Step S13: The alloy melt is atomized using an inert gas to obtain spherical powder.

[0029] Please see Figure 3 As shown, Figure 3 A flowchart illustrating the steps for determining the first comprehensive quality index in an embodiment of the present invention.

[0030] Specifically, in step S2, the process of determining the first comprehensive quality index includes: Step S21: Characterize first flowability data based on the flow time of the spherical powder; Step S22: Determine the first particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder; Step S23: The weighted summation result of the flow time and particle size distribution data is determined as the first comprehensive quality index.

[0031] In this embodiment of the invention, the first comprehensive quality index Q1 is calculated using the following formula: ; in, To normalize the flowability data, in this embodiment, a Hall effect flowmeter is used to measure the time it takes for 50g of powder to pass through a standard funnel, in seconds, and the normalization is calculated using the following formula. Normalize: ; For the ideal flow time, in this embodiment It lasts for 12 seconds; As normalized values ​​for particle size distribution data, in this embodiment, D10, D50, and D90 are measured using a laser particle size analyzer, and Span is calculated using the following formula to characterize the particle size distribution width of the spherical powder. The smaller the Span value, the more concentrated the distribution. ; Where D10 is the particle size corresponding to a cumulative particle size distribution percentage of 10%, that is, 10% of the powder particles have a particle size smaller than this value. D50, also known as median diameter, is the particle size at which the cumulative particle size distribution percentage reaches 50%. It represents the average particle size of the sample. D90 is the particle size corresponding to a cumulative particle size distribution percentage of 90%. Calculated using the following formula: ; in, In this embodiment, as the preset distribution width is, ; α and β are weighting coefficients, and α+β=1. In this embodiment, the weighting ratio is α=0.6 and β=0.4 to more accurately reflect the dominant influence of flowability on the stability of subsequent processes. Those skilled in the art will understand that the weighting coefficients can be adjusted according to actual process requirements, and are not limited to this embodiment.

[0032] It is understandable that the smaller the Span value, the smaller the difference between D90 and D10, the more concentrated the particle size distribution, and the more uniform the particle size. The larger the Span value, the wider the particle size distribution and the more uneven the particle size. In selective laser melting (SLM) additive manufacturing, the particle size distribution of the powder should be as concentrated as possible, i.e., the span value should be as small as possible, in order to form a dense powder layer, reduce porosity, and improve the quality of the formed parts.

[0033] Specifically, in step S2, determining whether to sieve the powder or return to step S1 to re-prepare it includes: The first comprehensive quality index is compared and analyzed with the first preset comprehensive quality index; Based on the result that the first comprehensive quality index is greater than or equal to the first threshold in the first preset comprehensive quality index, the screening treatment level is determined to be standard screening. Alternatively, based on the result that the first comprehensive quality index is less than the first threshold in the first preset comprehensive quality index and is greater than or equal to the second threshold in the first preset comprehensive quality index, the screening treatment level is determined to be medium-intensity screening. Alternatively, based on the result that the first comprehensive quality index is less than the second threshold in the first preset comprehensive quality index, the screening treatment level is determined to be high-intensity screening; Among them, the first threshold in the first preset comprehensive quality index is greater than the second threshold in the first preset comprehensive quality index.

[0034] In this embodiment of the invention, the first threshold value in the first preset comprehensive quality index is 85, and the second threshold value in the first preset comprehensive quality index is 75.

[0035] In this embodiment of the invention, the standard sieve has a mesh size of 30 μm, and the vibration time is 3 to 5 minutes. In this embodiment, the vibration time is 4 minutes. The medium-strength sieve has a screen aperture of 25μm and a vibration time of 5-8 minutes. In this embodiment, the vibration time is 6 minutes. The high-strength sieve has a mesh size of 20μm, a vibration time of 8-12 minutes, and an ultrasonic power of 100%-120% of the rated power. In this embodiment, the vibration time is 10 minutes and the ultrasonic power is 110%.

[0036] Specifically, the process of sieving powder includes: Step S251: Place the spherical powder into an ultrasonic vibrating sieve. Step S252: Set the sieve aperture to 15μm-45μm, and use the combined action of mechanical vibration and ultrasonic oscillation to make spherical powder pass through the sieve. Step S253: Collect the powder that passes through the sieve as qualified powder.

[0037] Understandably, agglomerates that did not pass through the sieve and some satellite powder were removed, while some ultrafine powder was also separated and removed under the action of vibration and airflow.

[0038] Please see Figure 4 As shown, Figure 4 A flowchart illustrating the steps for determining the second comprehensive quality index in an embodiment of the present invention.

[0039] Specifically, in step S3, the process of determining the second comprehensive quality index includes: Step S31: Determine the correction angle of the spherical powder after sieving based on the flow rate value of the spherical powder after sieving, and characterize the second flowability data. Step S32: Determine the second particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder after sieving. Step S33: Determine sphericity data based on the image of the spherical powder after sieving; Step S34: Compare and analyze the second flowability data, the second particle size distribution data, and the sphericity data with the corresponding preset threshold ranges, and determine the flowability score, particle size distribution score, and sphericity score based on the normalization results of the comparison analysis. Step S35: The weighted sum of the flowability score, particle size distribution score, and sphericity score is determined as the second comprehensive quality index.

[0040] In this embodiment of the invention, a Hall effect flowmeter is used to measure the flow time of spherical powder after sieving to characterize the second flowability data; The second comprehensive quality index Q2 is calculated using the following formula: ; in, The scores are flowability, particle size distribution, and sphericity, which are obtained by comparing the measured data with preset thresholds and linearly normalizing them to a 0-100 score scale. These are the weighting coefficients, and In this embodiment, ; Sphericity data was obtained through image analysis, specifically: Scanning electron microscope (SEM) images of at least 200 powder particles were randomly selected. The sphericity of each particle was calculated using image analysis software, and then the average value was taken. The sphericity was defined as... : ; Where A is the projected area of ​​the particle and P is the projected perimeter.

[0041] Specifically, in step S4, the process of determining the spherical powder usage strategy based on the second comprehensive quality index includes: The second comprehensive quality index is compared and analyzed with the second preset comprehensive quality index; Based on the result that the second comprehensive quality index is greater than or equal to the second threshold in the second preset comprehensive quality index, the selected area laser melting and forming strategy is determined. Alternatively, based on the result that the second comprehensive quality index is greater than or equal to the first threshold of the second preset comprehensive quality index and less than the second threshold of the second preset comprehensive quality index, the strategy of selecting degreasing followed by sintering is determined; Alternatively, based on the result that the second comprehensive quality index is less than the first threshold in the second preset comprehensive quality index, it is determined that the current batch of spherical powder is not suitable for molding, and the process returns to step S1.

[0042] In this embodiment of the invention, the second preset comprehensive quality index includes a first threshold and a second threshold, wherein the first threshold is set to 70 and the second threshold is set to 85; When Q2≥85, the powder quality is excellent, and selective laser melting is used for forming. When 70≤Q2<85, the powder quality is good, and it is sintered after debinding. When Q2 < 70, the powder is not suitable for this molding process.

[0043] Specifically, in step S5, the gas used in the cold spraying process is nitrogen, and the gas temperature is controlled within the range of 400℃ to 600℃, the gas pressure within the range of 3MPa to 5MPa, and the spraying distance within the range of 15mm to 25mm.

[0044] Specifically, in step S6, the process of determining the third comprehensive quality index includes: Step S61: Determine the porosity of the transition layer based on the microscopic image of the transition layer; Step S62: Determine the bonding strength based on the bonding strength between the transition layer and the substrate; Step S63: Construct a mathematical model based on porosity and bonding strength to calculate the third comprehensive quality index, wherein porosity is negatively correlated with the third comprehensive quality index and bonding strength is positively correlated with the third comprehensive quality index.

[0045] In this embodiment of the invention, based on the ASTM C633 standard, the bonding strength between the transition layer and the substrate is measured by an interfacial tensile test.

[0046] The third comprehensive quality index Q3 is calculated using the following formula to assess the quality of the transition layer: ; in, To achieve the actual porosity; In this embodiment, the maximum allowable porosity threshold is... ; This represents the actual bonding strength. In this embodiment, the minimum required bonding strength threshold is... .

[0047] Understandably, a mathematical model is constructed based on porosity and bonding strength to calculate the third comprehensive quality index, ensuring that the lower the porosity and the higher the bonding strength, i.e., the larger the Q3 value, the better the coating quality.

[0048] Specifically, in step S7, the process of determining the transition layer compensation strategy includes: The third comprehensive quality index is compared and analyzed with the third preset comprehensive quality index in real time. Based on the result that the third comprehensive quality index is greater than or equal to the third preset comprehensive quality index, the first-level parameter adjustment strategy is determined to be adopted. Alternatively, based on the result that the third comprehensive quality index is less than the third preset comprehensive quality index, a secondary parameter adjustment strategy may be adopted.

[0049] In this embodiment of the invention, a third preset comprehensive quality index is set to 85. The passability of the transition layer is evaluated in real time based on the third comprehensive quality index. When the third comprehensive quality index is greater than or equal to the third preset comprehensive quality index, the transition layer is deemed to be qualified; otherwise, it is deemed to be unqualified, and a transition layer compensation strategy is executed.

[0050] In this embodiment, the primary parameter adjustment strategy is designed for minor deviations: When the third comprehensive quality index is unqualified, but the porosity is not qualified... Or the strength of the bonding surface When only one indicator deviates from the preset threshold, or when the deviations of both indicators are small, the first-level parameter adjustment strategy is triggered. This strategy adjusts single or dual parameters based on the dominant deviation principle, specifically as follows: If the porosity is the dominant deviation: that is In such cases, prioritize adjusting the gas temperature or spraying distance; Gas temperature adjustment amount ; Spraying distance adjustment amount ; in, The target porosity is usually set to . In this embodiment, 50%–80% ; In this embodiment, the temperature compensation coefficient is used. ; The distance compensation coefficient is used in this embodiment. The negative sign indicates increasing the distance to reduce the porosity. It can be adjusted individually or simultaneously.

[0051] If the bonding strength is the dominant deviation: that is At that time, the gas temperature should be adjusted first.

[0052] Gas temperature adjustment amount ; in, The target binding strength is usually set to . In this embodiment, the percentage is 110%–130%. ; In this embodiment, the temperature compensation coefficient is used. Increasing the temperature can increase the kinetic energy of the particles and improve the bonding strength.

[0053] In this embodiment, the secondary parameter adjustment strategy (for severe deviations) When the third comprehensive quality index Q3 is severely unqualified, or the effect of adjusting the first-level parameters is not significant, the second-level parameter adjustment strategy is triggered. This strategy generates a synergistic effect by simultaneously adjusting the gas temperature, gas pressure, and spraying distance to quickly correct quality deviations. The calculation of the adjustment amount is based on an extension of the first-level strategy and incorporates pressure adjustment: Gas temperature adjustment amount ; Gas pressure adjustment ; Spraying distance adjustment amount ; in, This is the compensation coefficient for the secondary strategy.

[0054] In this embodiment: ; The negative sign indicates that reducing pressure helps to reduce voids. .

[0055] After completing the parameter adjustments, continue with cold spraying and update the third comprehensive quality index in real time until... The transition layer was deemed qualified.

[0056] To illustrate the technical effects of the present invention in detail, a comparative analysis is provided below using specific embodiments and comparative examples. All embodiments and comparative examples were conducted under the same basic equipment and environment to ensure the fairness of the comparison.

[0057] Example 1 A high-toughness metal-ceramic composite material component is prepared according to the method of the present invention, and the specific steps are as follows: Raw material proportioning and powder preparation S1: Weigh out a mixture of raw materials including 10% Co, 6% Cr, 3% TaC, 1.5% VC, and the balance being WC by weight percentage. Prepare spherical powder using an inert gas atomization method.

[0058] First Comprehensive Quality Index Judgment and Screening S2: The flow time of the original powder was measured to be 11.8 seconds, with particle size distributions of D10 = 28 μm, D50 = 35 μm, and D90 = 45 μm. The calculated Span value was 0.486. After normalization, the first comprehensive quality index Q1 was 92. Since Q1 ≥ 85 (the first threshold), a standard sieve with a mesh size of 30 μm was used, and the powder was vibrated for 4 minutes.

[0059] Second Comprehensive Quality Index Determination and Forming Strategy Selection (S3, S4): After sieving, the flow time, particle size distribution concentration, and sphericity of the powder were optimized, and the second comprehensive quality index Q2 was calculated to be 88. Since Q2 ≥ 85 (the second threshold), the powder quality was deemed excellent, and a selective laser melting (SLM) forming strategy was adopted to obtain a dense SLM-formed part.

[0060] Transition layer preparation and mass compensation: Ni-Co-Cr-Al-Y alloy powder was sprayed onto the SLM-formed substrate using a cold spray process. The gas temperature was 500℃, the pressure was 4MPa, and the distance was 20mm. Real-time monitoring showed that after the first spray, the porosity of the transition layer was 1.8%, and the bonding strength was 55MPa. The calculated third comprehensive quality index Q3 = (1 - 1.8% / 2%) × (55 / 50) × 100 = 91. Q3 > 85 (the third preset value), so the transition layer was deemed qualified, and spraying was stopped.

[0061] Example 2 The raw material ratio was changed, and Co 8%, Cr 8%, TaC 2%, VC 2%, with the remainder being WC were weighed out as a percentage by weight. In step S2, the original powder Q1 was measured to be 78, which is a medium-quality powder (75≤Q1<85), so a medium-strength sieving method was used (sieve aperture 25μm, vibration for 6 minutes). After sieving, the powder Q2 was 76, which is good quality but not optimal (70≤Q2<85), so an adaptive debinding and sintering strategy was selected. The subsequent transition layer preparation was similar to that in Case 1, and the final Q3 was 87, which is of acceptable quality.

[0062] Example 3: An example of applying a compensation strategy After the SLM-molded part is prepared, a cold spray transition layer is applied. The initial process parameters are set as follows: gas temperature 500℃, gas pressure 4.0MPa, and spraying distance 20mm.

[0063] Initial Coating and Evaluation: The transition layer of the initial coating is inspected, and the porosity is measured. bonding strength .

[0064] Quality Judgment and Strategy Triggering: Calculating the Third Comprehensive Quality Index .

[0065] because The transition layer was deemed unqualified.

[0066] Analysis of bias: ; Since 1.4 > 1.04, the porosity is determined to be the dominant deviation, and the Q3 value is low, thus triggering the secondary parameter adjustment strategy.

[0067] Parameter compensation: set up .

[0068] Calculate the adjustment amount: ; The adjusted parameters are: gas temperature 530℃, gas pressure 4.38MPa, and spraying distance 18.7mm.

[0069] Recoating and Closed-Loop Verification: Coating was continued using the new parameters. The porosity was measured again. bonding strength .

[0070] calculate .

[0071] because The transition layer is of acceptable quality; therefore, the cold spraying process should be discontinued.

[0072] Comparative Example 1, without using the first comprehensive quality index and dynamic screening. The original powder was prepared using the same raw materials and atomization process as in Example 1. However, the first comprehensive quality index was not calculated; instead, standard sieving (30 μm pore size, vibration for 4 minutes) was used for processing. Because this batch of powder actually contained a small amount of fine powder agglomerates, standard sieving failed to effectively remove them, resulting in limited improvement in the sphericity and flowability of the powder after sieving.

[0073] Comparative Example 2, without using the second comprehensive quality index and adaptive molding strategy The powder was sieved using the same method as in Comparative Example 1. However, the second comprehensive quality index was not calculated; instead, a selective laser melting (SLM) forming strategy was consistently employed. Because the powder quality did not meet the optimal requirements of the SLM process, spatter and micropores occurred during the forming process.

[0074] Comparative Example 3, without using the third comprehensive quality index and real-time compensation The same substrate and powder as in Example 1 were used. During cold spraying, a fixed set of parameters (gas temperature 450°C, pressure 3.5 MPa, distance 22 mm) were used without real-time quality assessment or parameter compensation. After spraying, the transition layer porosity was found to be 3.5%, and the bonding strength was 42 MPa.

[0075] Comparative Example 4: Fixed Parameter Comparison Without Compensation Strategy Cold spraying was performed using the same substrate, powder, and initial process parameters as in Example 3 (gas temperature 500°C, pressure 4.0 MPa, distance 20 mm), but without real-time quality assessment and parameter compensation, until the coating reached the predetermined thickness. After spraying, the transition layer porosity was found to be 3.1%, and the bonding strength was 45 MPa.

[0076] The components or intermediate products prepared in the above embodiments and comparative examples were subjected to performance testing, and the results are shown in Table 1. Table 1 contains the experimental data of Examples 1-2 and Comparative Examples 1-3: Table 1 ; Analysis and Conclusion: 1. The effect of dynamic powder sieving and quality access: Example 1 uses the Q1 index to accurately identify powder quality and match sieving intensity to obtain high-quality powder with a density of up to 99.5% for its SLM molded parts.

[0077] Comparative Example 1 used fixed sieving, which failed to effectively address the defects in the original powder, resulting in significantly lower density and mechanical properties of the molded parts compared to Example 1. This demonstrates that dynamic sieving based on the first comprehensive quality index is crucial for improving the fundamental properties of materials.

[0078] 2. The effect of the adaptive molding strategy: After sieving, the powder in Example 2 had a Q2 value of 76. The system adaptively selected the debinding and sintering process, resulting in a final component with good performance and a high yield.

[0079] Comparative Example 2, which forcibly employed the SLM process despite powder quality mismatch, resulted in a sharp decline in density and mechanical properties, with a yield as low as 75%. This highlights the significant advantages of the adaptive molding strategy based on the second comprehensive quality index in ensuring yield and optimizing resources.

[0080] 3. The effect of real-time quality closed-loop control in the transition layer: Example 1 obtained a high-quality transition layer with low porosity and high bonding strength through real-time monitoring and compensation.

[0081] Comparative Example 3, using fixed parameters, shows a poor transition layer quality (high porosity and low bonding strength), which will become a weak link in the component's service life. This confirms the decisive role of the real-time compensation strategy based on the third comprehensive quality index in ensuring interfacial bonding strength and component reliability.

[0082] The components or intermediate products prepared in the above embodiments and comparative examples were subjected to performance testing, and the results are shown in Table 2. Table 2 shows the experimental data of Example 3 and Comparative Example 4: Table 2 ; A comparison of Example 3 and Comparative Example 4 shows that the real-time quality assessment and multi-level parameter compensation strategy proposed in this invention can proactively and accurately bring deviating processes back on track, significantly improving the density and bonding strength of the transition layer, thereby systematically ensuring the high reliability of the component interface bonding force. This not only proves the effectiveness of the compensation strategy but also highlights the advantages of the intelligent quality control throughout the entire process of this invention compared to traditional fixed parameter methods.

[0083] In summary, through thorough comparison of the examples and comparative examples, the experimental data strongly demonstrates that the preparation method provided by this invention systematically solves the core problems pointed out in the background art, such as unstable powder quality, single molding process, and weak interfacial bonding, through dynamic quality assessment and intelligent decision compensation throughout the entire process. Ultimately, it achieves high-efficiency, high-yield, and waste-free preparation of high-toughness, high-reliability metal-ceramic composite material components.

[0084] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0085] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing high-toughness metal-ceramic composite material components for laser selective melting, characterized in that, Includes the following steps: Step S1: Using a preset weight percentage of Co, Cr, TaC, VC and the remaining weight percentage of WC as raw materials, spherical powder is prepared by atomization with inert gas. Step S2: Based on the first flowability data and the first particle size distribution data of the spherical powder, determine the first comprehensive quality index of the spherical powder to determine the sieving treatment level, and perform sieving treatment on the spherical powder using the sieving treatment parameters corresponding to the sieving treatment level, wherein the sieving treatment level includes standard sieving, medium-strength sieving, and high-strength sieving. Step S3: Based on the second flowability data, second particle size distribution data, and sphericity data of the spherical powder after sieving, determine the flowability score, particle size distribution score, and sphericity score respectively to determine the second comprehensive quality index. Step S4: Determine the spherical powder usage strategy based on the second comprehensive quality index to obtain SLM molded parts, wherein the spherical powder usage strategy includes selective laser melting molding and sintering molding after debinding; Step S5: Using a cold spraying process, Ni-Co-Cr-Al-Y series alloy powder is sprayed onto the substrate surface to form a transition layer; Step S6: Determine the third comprehensive quality index based on the porosity and bonding strength of the transition layer during the cold spraying process; Step S7: Based on the third comprehensive quality index, the passability of the transition layer is evaluated in real time. If the transition layer is found to be unqualified, a transition layer compensation strategy is determined to be implemented until the transition layer is qualified. Then, the cold spraying process is stopped to complete the preparation. The compensation strategy includes a primary parameter adjustment strategy based on the relative deviation between the porosity and the bonding strength of the transition layer, which determines the adjustment of the gas temperature or spraying distance, and a secondary parameter adjustment strategy that simultaneously adjusts the gas temperature, pressure and spraying distance.

2. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 1, characterized in that, In step S1, the process of preparing spherical powder by inert gas atomization includes: Step S11: Weigh out 5%–15% Co, 3%–10% Cr, 1%–5% TaC, 0.5%–3% VC, and the remaining weight percentage of WC according to the weight percentage to obtain mixed raw materials; Step S12: The mixed raw materials are put into a vacuum induction melting furnace and heated to a molten state under inert gas protection to obtain an alloy melt; Step S13: The alloy melt is atomized using the inert gas to obtain the spherical powder.

3. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 2, characterized in that, In step S2, the process of determining the first comprehensive quality index includes: Step S21: Characterize the first flowability data based on the flow time of the spherical powder; Step S22: Determine the first particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder; Step S23: The weighted sum of the flow time and the particle size distribution data is determined as the first comprehensive quality index.

4. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 3, characterized in that, In step S2, the process of determining the screening treatment level includes: The first comprehensive quality index is compared and analyzed with the first preset comprehensive quality index; Based on the result that the first comprehensive quality index is greater than or equal to the first threshold in the first preset comprehensive quality index, the screening process level is determined to be standard screening. Alternatively, based on the result that the first comprehensive quality index is less than the first threshold in the first preset comprehensive quality index and is greater than or equal to the second threshold in the first preset comprehensive quality index, the screening treatment level is determined to be medium-intensity screening. Alternatively, based on the result that the first comprehensive quality index is less than the second threshold in the first preset comprehensive quality index, the screening process level is determined to be high-intensity screening; Wherein, the first threshold in the first preset comprehensive quality index is greater than the second threshold in the first preset comprehensive quality index.

5. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 4, characterized in that, The powder sieving process includes: Step S251: Place the spherical powder into an ultrasonic vibrating sieve. Step S252: Set the sieve aperture to 15μm-45μm, and use the combined action of mechanical vibration and ultrasonic oscillation to make the spherical powder pass through the sieve. Step S253: Collect the powder that passes through the sieve as qualified powder.

6. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 5, characterized in that, In step S3, the process of determining the second comprehensive quality index includes: Step S31: Determine the correction angle of the spherical powder after sieving based on the flow rate value of the spherical powder after sieving, and characterize the second flowability data; Step S32: Determine the second particle size distribution data based on the D10, D50 and D90 values ​​of the spherical powder after sieving. Step S33: Determine the sphericity data based on the image of the spherical powder after sieving; Step S34: Compare and analyze the second flowability data, the second particle size distribution data, and the sphericity data with the corresponding preset threshold ranges, and determine the flowability score, the particle size distribution score, and the sphericity score based on the normalization results of the comparison and analysis results. Step S35: The weighted sum of the flowability score, the particle size distribution score, and the sphericity score is determined as the second comprehensive quality index.

7. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 6, characterized in that, In step S4, the process of determining the spherical powder usage strategy based on the second comprehensive quality index includes: The second comprehensive quality index is compared and analyzed with the second preset comprehensive quality index; Based on the result that the second comprehensive quality index is greater than or equal to the second threshold in the second preset comprehensive quality index, the selected area laser melting forming strategy is determined. Alternatively, based on the result that the second comprehensive quality index is greater than or equal to the first threshold of the second preset comprehensive quality index and less than the second threshold of the second preset comprehensive quality index, the strategy of degreasing and then sintering is determined. Alternatively, based on the result that the second comprehensive quality index is less than the first threshold in the second preset comprehensive quality index, it is determined that the current batch of spherical powder is not suitable for molding, and the process returns to step S1.

8. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 7, characterized in that, In step S5, the gas used in the cold spraying process is nitrogen, and the gas temperature is controlled within the range of 400℃ to 600℃, the gas pressure within the range of 3MPa to 5MPa, and the spraying distance within the range of 15mm to 25mm.

9. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 8, characterized in that, In step S6, the process of determining the third comprehensive quality index includes: Step S61: Determine the porosity of the transition layer based on the microscopic image of the transition layer; Step S62: Determine the bonding strength based on the bonding strength between the transition layer and the substrate; Step S63: Construct a mathematical model based on the porosity and the bonding surface strength to calculate the third comprehensive quality index, wherein the porosity is negatively correlated with the third comprehensive quality index and the bonding surface strength is positively correlated with the third comprehensive quality index.

10. The method for preparing high-toughness metal-ceramic composite material components for laser selective melting according to claim 9, characterized in that, In step S7, the process of determining the transition layer compensation strategy includes: The third comprehensive quality index is compared and analyzed with the third preset comprehensive quality index in real time. Based on the result that the third comprehensive quality index is greater than or equal to the third preset comprehensive quality index, the first-level parameter adjustment strategy is determined to be adopted. Alternatively, based on the result that the third comprehensive quality index is less than the third preset comprehensive quality index, the secondary parameter adjustment strategy is determined to be adopted.

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