A selective laser melting manufacturing method for particle-reinforced titanium-based composite components

Abstract

The present invention discloses a selective laser melting manufacturing method for particle reinforced titanium-based composite material components. The method controls the energy input of the preheating laser and the forming laser during the forming process, so that the stress generated in the composite material component is fully released above its low plastic zone temperature range, thereby avoiding cracks in the component during the selective laser melting manufacturing process or after the manufacturing is completed. The steps of the method are as follows: optimizing the selective laser melting process of the composite material to obtain the forming process parameters of a simple structure without cracks and measuring the low plastic temperature range of the material; based on the optimized process parameters, adjusting the laser power and scanning speed of the preheating laser to keep the powder bed temperature above the low plastic temperature range of the composite material; completing the manufacturing of the first layer according to the preset scanning path; repeating the preheating and selective laser melting processes to complete the manufacturing of the particle reinforced titanium-based composite material component; after the formed component is cooled, a crack-free particle reinforced titanium-based composite material component is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal additive manufacturing, and in particular relates to a selective laser melting manufacturing method for particle reinforced titanium-based composite material components. Background Art

[0002] Compared to titanium alloys, particle-reinforced titanium-based composites (PRCs) offer superior wear resistance, strength, and modulus, potentially expanding the application of titanium alloys. However, PRCs suffer from disadvantages such as poor thermal conductivity, high chemical activity, and high deformation resistance, making them typically difficult to machine. Selective laser melting (SLM) technology enables the rapid, moldless, high-density, and integrated near-net-net-net formation of high-performance, complex metal components. This technology holds broad application prospects in aerospace, aviation, healthcare, and consumer electronics, attracting significant attention and attention from the industry and considered an ideal processing method for titanium alloys and composites. Currently, research and application of SLM (selective laser melting) of titanium alloys are relatively mature. However, due to the greater strength and modulus of PRCs, the rapid heating and cooling processes of SLM generate greater stresses. Consequently, most PRCs can only be used to form simple structures under laboratory conditions. Complex components with sudden changes in cross-sectional area are prone to stress concentration at these locations, leading to microcracks or even complete cracking of the composite component during cooling. This is a major obstacle to the transition of SLM PRCs from laboratory to practical application.

[0003] In order to solve the problem of cracks easily occurring in the selective laser melting process of difficult-to-process particle reinforced titanium matrix composite components, the substrate is usually preheated, but the overall effect is not good. On the one hand, the substrate preheating temperature of the current commercial selective laser melting equipment is generally lower than 200 o C, and the effect of substrate preheating decays severely along the deposition height direction; on the other hand, the selection of preheating temperature does not fully consider the law of material properties changing with temperature. When the plasticity of the material is poor within the selected preheating temperature range, it cannot effectively solve the deformation and cracking problems of particle-reinforced titanium-based composites and components. Summary of the Invention

[0004] The main purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a selective laser melting method for manufacturing a particle-reinforced titanium-based composite material component and a particle-reinforced titanium-based composite material component obtained by the selective laser melting method. The method adopts a dual beam of preheating laser and forming laser, and by synergistically controlling the energy input of the preheating laser and the forming laser during the forming process, the stress generated inside the particle-reinforced titanium-based composite material component is fully released above the low plastic zone temperature range of the material, thereby avoiding cold cracks in the component during cooling to room temperature.

[0005] In order to achieve the above first object, the present invention adopts the following technical solutions:

[0006] A selective laser melting manufacturing method for difficult-to-process particle-reinforced titanium-based composite material components comprises the following steps: first, the selective laser melting process is optimized for the particle-reinforced titanium-based composite material to obtain crack-free single-pass forming process parameters; the tensile properties at different temperatures are measured according to the metal material tensile test method to determine the low plasticity temperature range of the material (the temperature range in which the elongation is less than 5%); based on the selective laser melting process parameters, the laser power and scanning speed of the preheating laser are adjusted to keep the powder bed temperature above the low plasticity temperature range of the printed material while avoiding powder sintering; then, the optimized selective laser melting process parameters are used to complete the manufacturing of the first layer according to a preset scanning path; the preheating and selective laser melting processes are repeated to complete the manufacturing of the particle-reinforced titanium-based composite material component; finally, the formed component is naturally cooled to room temperature to obtain a crack-free particle-reinforced titanium-based composite material component.

[0007] The selective laser melting method for manufacturing the difficult-to-process particle-reinforced titanium-based composite material component comprises the following steps:

[0008] S1. In an inert gas chamber, optimizing the selective laser melting process for a particle-reinforced titanium-based composite material to obtain crack-free, single-pass forming process parameters, including the laser power and scanning speed of the preheating laser and the forming laser;

[0009] S2. Under normal conditions, prepare the tensile specimens using the optimized process parameters above, and test their tensile plasticity at different temperatures to identify the temperature range where the elongation is less than 5%;

[0010] S3. Based on the forming process parameters, adjust the laser power and scanning speed of the preheating laser, scan the entire powder bed width, and keep the powder bed temperature above the low plastic temperature range of the composite material;

[0011] S4. Based on the forming process parameters, adjust the laser power and scanning speed of the forming laser and complete the manufacturing of the first layer according to the preset scanning path;

[0012] S5, repeating steps S3 and S4 to complete the multi-layer manufacturing of the particle reinforced titanium-based composite material component;

[0013] S6. After the manufacturing is completed, the formed component is naturally cooled to room temperature to obtain a crack-free particle reinforced titanium-based composite material component.

[0014] Furthermore, the reinforcing particles used in the particle-reinforced titanium-based composite material are ceramic materials including TiC (titanium carbide), SiC (silicon carbide) or TiB (titanium boride), or high-melting-point metals such as W (tungsten), and the scale of the reinforcing particles is nanometer or micrometer level.

[0015] Furthermore, the titanium matrix in the particle-reinforced titanium-based composite material is pure titanium or a titanium alloy, and the titanium alloy is selected from one of α titanium alloy, β titanium alloy and α+β titanium alloy.

[0016] Furthermore, in step S3, the preheating laser power is 1000W to 3000W, the spot diameter is 1mm to 5mm, and the scanning speed is 0.1m / s to 2m. Applying the preheating laser within this parameter range can keep the temperature of the powder bed and the formed part above the low plasticity zone of the material to release stress, while preventing powder melting or sintering.

[0017] Furthermore, in step S3, the powder bed temperature is obtained by thermocouple or infrared thermal imaging technology and adjusted by PID (proportional-integral-differential) so that the temperature of the powder bed and the formed part is always maintained above the low plastic temperature zone of the material.

[0018] Furthermore, in step S2, the low plasticity temperature range of the composite material is determined based on the tensile plasticity of the composite material at different temperatures, and the elongation is less than 5% for low plasticity. When the elongation of the material is higher than 5%, the cracking sensitivity of the component at this temperature will be greatly reduced. The tensile plasticity of the composite material at different temperatures is obtained according to the tensile test standard of metal materials. The test temperature starts from room temperature and increases by 20 o C~50 o C was tested, and the temperature range where the elongation was less than 5% was determined based on the test results.

[0019] Furthermore, in step S4, the laser power of the forming laser is 200W to 1000W, the spot diameter is 20μm to 100μm, and the scanning speed is 0.1m / s to 5m / s. Forming within this parameter range can reduce porosity and poor fusion defects in the formed part, ensuring that the composite material maintains good metallurgical quality.

[0020] Furthermore, the number of scans of the preheating laser in step S3 is one or more according to the temperature measurement result, so as to ensure that the temperature of the powder bed is above the low plastic temperature range of the composite material.

[0021] Furthermore, the energy density of the preheating laser is lower than that of the forming laser, which avoids melting or sintering of the powder during preheating, thereby ensuring the geometric accuracy of the formed part and reducing the workload of removing the bonding powder in the post-processing process.

[0022] In order to achieve the above second purpose, the present invention adopts the following technical solutions:

[0023] A particle reinforced titanium-based composite material component is prepared by adopting the selective laser melting manufacturing method of the particle reinforced titanium-based composite material component.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] (1) The selective laser melting manufacturing method for difficult-to-process particle reinforced titanium-based composite material components provided by the present invention can fully release the stress generated inside the particle reinforced titanium-based composite material components above the low plastic zone temperature range of the material by synergistically controlling the energy input of the preheating laser and the forming laser during the forming process, thereby avoiding the generation of cold cracks during the selective laser melting manufacturing process or after the manufacturing is completed, thereby realizing the selective laser melting manufacturing of crack-free particle reinforced titanium-based composite material components.

[0026] (2) The selective laser melting method for manufacturing difficult-to-process particle-reinforced titanium-based composite components provided by the present invention performs forming above the low plasticity temperature range of the material. Under these temperature conditions, the stress of the manufacturing process can be fully released. At the same time, the microstructure of the composite material will also fully evolve, achieving in-situ control of the composite material's microstructure, thereby reducing energy consumption in the subsequent heat treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0028] Figure 1 The 1wt% nano-TiC reinforced TC4 alloy composite material component in Example 1 of the present invention;

[0029] Figure 2 Schematic diagram of the composite material component in Comparative Example 1 of the present invention;

[0030] Figure 3 The 2wt% micron TiB reinforced TA15 alloy composite material component in Example 2 of the present invention;

[0031] Figure 4 Schematic diagram of a composite material component in Comparative Example 2 of the present invention;

[0032] Figure 5 This is a process step diagram of a selective laser melting manufacturing method for a difficult-to-process particle-reinforced titanium-based composite material component disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0034] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0035] Example 1

[0036] like Figure 5 As shown, this embodiment specifically discloses a selective laser melting method for manufacturing a 1wt% nano-TiC reinforced TC4 alloy composite material component. The steps of the selective laser melting method are as follows:

[0037] S1. Optimization of the selective laser melting process for a 1wt% nano-TiC-reinforced TC4 alloy composite material yielded crack-free, single-pass forming parameters: laser power 230W, scanning speed 800mm / s, and spot diameter 80μm. The forming process was performed under argon atmosphere using the TC4 alloy as the substrate.

[0038] S2. The above-mentioned optimized process parameters were used to prepare the tensile specimens. After machining, the tensile properties of the specimens were measured at different temperatures according to the metal material tensile test method. It was found that the temperature range in which the elongation of the 1wt% nano-TiC reinforced TC4 alloy composite material was less than 5% was room temperature ~ 360°C.

[0039] S3. Based on the optimized forming process parameters, adjust the preheating laser spot diameter (3mm), laser power (2000W) and scanning speed (1200mm / s), scan the entire powder bed, and the powder bed temperature measured by the infrared thermometer is maintained at 360~400 o C, the corresponding material elongation is 5~7.2%, which does not belong to the low plasticity temperature range of the material;

[0040] S4. Optimized crack-free single-pass forming process parameters were used: laser power 230W, scanning speed 800mm / s, and spot diameter 80μm. Slicing and path planning were performed based on the 3D model of the formed part, and the first layer scan was completed according to the preset scanning path.

[0041] S5, repeating steps S3 and S4 to complete the manufacture of the particle reinforced titanium-based composite material component;

[0042] S6. After the manufacturing is completed, the formed component is naturally cooled to room temperature to obtain a crack-free particle reinforced titanium matrix composite component, such as Figure 1 shown.

[0043] Comparative Example 1

[0044] The selective laser melting process of 1wt% nano-TiC reinforced TC4 alloy composite material was optimized to obtain the crack-free single-pass forming process parameters: laser power 230W, scanning speed 800mm / s, and spot diameter 80μm. The component was manufactured using the above optimized selective laser melting process parameters according to the preset scanning path. The infrared thermometer measured that the powder bed temperature was maintained at 80~300℃ during the forming process. o C, the corresponding material elongation is 0.2~4.5%, which belongs to the low plastic temperature range of the material; after forming, the formed component is naturally cooled to room temperature to obtain a cracked 1wt% nano-TiC reinforced TC4 alloy composite component, such as Figure 2 shown.

[0045] It can be seen from the 1wt% nano-TiC reinforced TC4 alloy composite components obtained in Example 1 and Comparative Example 1 that a crack-free 1wt% nano-TiC reinforced TC4 alloy composite component can be obtained by adopting the method provided by the present invention.

[0046] Example 2

[0047] like Figure 5 As shown, this embodiment further specifically discloses another selective laser melting method for manufacturing a 2wt% micron TiB reinforced TA15 alloy composite material component. The steps of the selective laser melting method are as follows:

[0048] S1. Optimizing the selective laser melting process for a 2wt% TiB-reinforced TA15 alloy composite material yielded crack-free, single-pass forming parameters: laser power 350W, scan speed 900mm / s, and spot diameter 80μm. The forming process was performed under argon atmosphere using the TA15 alloy as the substrate.

[0049] S2. The above-mentioned optimized process parameters were used to prepare the tensile specimens. After machining, the tensile properties of the specimens were measured at different temperatures according to the metal material tensile test method. It was found that the temperature range in which the elongation of the 2wt% nano-TiB reinforced TA15 alloy composite material was less than 5% was room temperature ~ 460°C.

[0050] S3. Based on the optimized forming process parameters, the spot diameter (3mm), laser power (2800W) and scanning speed (1000mm / s) of the preheating laser were adjusted. The entire powder bed was scanned. The temperature of the powder bed was measured by the infrared thermometer and was between 460°C and 500°C. o C, the corresponding material elongation is 5~6.5%, which does not belong to the low plastic temperature range of the material;

[0051] S4. Optimized crack-free single-pass forming process parameters were used: laser power 350W, scanning speed 900mm / s, and spot diameter 80μm. Slicing and path planning were performed based on the 3D model of the formed part, and the first layer scan was completed according to the preset scanning path.

[0052] S5. Repeat steps S3 and S4 to complete the manufacture of the TiB reinforced TA15 alloy composite material component. According to the test, the density of the formed part reaches 99.8% when the forming parameters are used;

[0053] S6. After the manufacturing is completed, the formed component is naturally cooled to room temperature to obtain a crack-free particle reinforced titanium matrix composite component, such as Figure 1 shown.

[0054] Comparative Example 2

[0055] The selective laser melting process of 2wt% micron TiB reinforced TA15 alloy composite material was optimized to obtain crack-free single-pass forming process parameters: laser power 350W, scanning speed 900mm / s, spot diameter 80μm; the component was manufactured using the above optimized selective laser melting process parameters according to the preset scanning path; the powder bed temperature measured by infrared thermometer was maintained at 100~430℃ during the forming process. o C, the corresponding material elongation is 0.2~4.7%, which belongs to the low plasticity temperature range of the material; the formed component is naturally cooled to room temperature to obtain a cracked 2wt% nano-TiB reinforced TA15 alloy composite component, such as Figure 4 shown.

[0056] It can be seen from the 2wt% micron TiB reinforced TA15 alloy composite components obtained in Example 2 and Comparative Example 2 that a crack-free 2wt% micron TiB reinforced TA15 alloy composite component can be obtained by adopting the method provided by the present invention.

[0057] In summary, by comparing the above embodiments and comparative examples, it can be seen that the method provided by the present invention avoids cold cracks generated in the particle-reinforced titanium-based composite material during or after the selective laser melting manufacturing process, thereby realizing the selective laser melting manufacturing of crack-free particle-reinforced titanium-based composite material components.

[0058] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0059] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A selective laser melting method for manufacturing a particle reinforced titanium-based composite material component, characterized in that: The selective laser melting manufacturing method comprises the following steps: S1. Optimization of the selective laser melting process for 1wt% nano-TiC reinforced TC4 alloy composites yielded crack-free single-pass forming process parameters: laser power 230W, scanning speed 800mm / s, spot diameter 80μm, TC4 alloy as the substrate, and the forming process was carried out in an argon atmosphere. S2. Prepare tensile specimens using the optimized process parameters. After machining, measure their tensile properties at different temperatures according to the metal material tensile test method. The temperature range in which the elongation of the 1wt% nano-TiC reinforced TC4 alloy composite material is less than 5% is room temperature to 360°C. S3. Based on the optimized forming process parameters, the preheating laser spot diameter is 3mm, the laser power is 2000W and the scanning speed is 1200mm / s. The entire powder bed is scanned to keep the powder bed temperature at 360~400 o C, the corresponding material elongation is 5~7.2%; S4. Optimized crack-free single-pass forming process parameters were used: laser power 230W, scanning speed 800mm / s, and spot diameter 80μm. Slicing and path planning were performed based on the 3D model of the formed part, and the first layer scan was completed according to the preset scanning path. S5, repeating the preheating laser scanning of the entire powder bed width in step S3 and the forming scanning in S4 to complete the manufacturing of the particle reinforced titanium matrix composite material component; S6. After the manufacturing is completed, the formed component is naturally cooled to room temperature to obtain a crack-free particle reinforced titanium-based composite material component.

2. A selective laser melting method for manufacturing particle-reinforced titanium-based composite components, characterized in that: The selective laser melting manufacturing method comprises the following steps: S1. Optimization of the selective laser melting process for 2wt% TiB-reinforced TA15 alloy composites yielded crack-free single-pass forming process parameters: laser power 350W, scanning speed 900mm / s, spot diameter 80μm, with TA15 alloy as the substrate, and the forming process was carried out in an argon atmosphere. S2. Prepare tensile specimens using the optimized process parameters. After machining, measure their tensile properties at different temperatures according to the metal material tensile test method. The temperature range in which the elongation of the 2wt% nano-TiB reinforced TA15 alloy composite material is less than 5% is room temperature to 460°C. S3. Based on the optimized forming process parameters, the spot diameter of the preheating laser is 3mm, the laser power is 2800W and the scanning speed is 1000mm / s. The entire powder bed is scanned to keep the powder bed temperature at 460~500 o C, the corresponding material elongation is 5~6.5%; S4. Optimized crack-free single-pass forming process parameters were used: laser power 350W, scanning speed 900mm / s, and spot diameter 80μm. Slicing and path planning were performed based on the 3D model of the formed part, and the first layer scan was completed according to the preset scanning path. S5, repeating the preheating laser scanning of the entire powder bed width in step S3 and the forming scanning in S4 to complete the manufacturing of the particle reinforced titanium matrix composite material component; S6. After the manufacturing is completed, the formed component is naturally cooled to room temperature to obtain a crack-free particle reinforced titanium-based composite material component.

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