Titanium carbide and elemental powder modification method for 5-series aluminum alloys and aluminum alloy composites
By adding titanium carbide and elemental powders to 5-series aluminum alloy powder and combining selective laser melting technology, the problems of crack defects and poor densification effect in additive manufacturing of 5-series aluminum alloys were solved, and high-strength, dense aluminum alloy composite materials were prepared.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NORTHWESTERN POLYTECHNICAL UNIV
- Filing Date
- 2024-09-19
- Publication Date
- 2026-08-04
AI Technical Summary
In additive manufacturing, 5-series aluminum alloys are difficult to manufacture due to their high Mg content. Furthermore, aluminum alloy composites suffer from crack defects and poor densification due to hot cracking and the evaporation of strengthening elements.
Aluminum alloy composite materials were prepared by mixing titanium carbide particles and elemental powders into 5-series aluminum alloy powder, uniformly dispersing the titanium carbide particles on the powder surface, and then subjecting the mixture to heat preservation and sieving. Selective laser melting and forming were then carried out, and the laser parameters and forming chamber pressure were controlled.
The strength and density of aluminum alloy composite materials were improved, hot cracking was eliminated, and aluminum alloy materials with dense structure, no cracks, fine grains and isotropic properties were prepared, which reduced the difficulty of additive manufacturing.
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Figure CN119082562B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of additive manufacturing technology, and more specifically, to a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, and to aluminum alloy composite materials. Background Technology
[0002] Additive manufacturing (AM), also known as 3D printing, is an emerging manufacturing technology that uses digital models as a basis to build up materials layer by layer to create physical objects. It embodies the close integration of information network technology, advanced materials technology, and digital manufacturing technology, and is an important component of advanced manufacturing.
[0003] Selective laser melting (LPBF) is one of the most commonly used and effective additive manufacturing technologies for producing metal parts. It uses a computer-aided design model, where a high-energy laser beam melts the powder during the printing process, which then solidifies at an extremely rapid cooling rate. Employing a layer-by-layer melting and stacking method, it can produce customized parts with virtually unlimited design freedom. Since the component model comes from the computer design, this manufacturing technology eliminates the need for molds, shortening the production cycle and reducing material waste.
[0004] Aluminum alloys, as typical lightweight alloys, possess advantages such as low density, high specific strength, high thermal conductivity, and ease of processing. Commercially produced high-strength aluminum alloys are widely used in aerospace, marine, and automotive industries. 5-series aluminum alloys, with their excellent corrosion resistance, lack of low-temperature brittleness, and magnetism, are extensively used in ship hull structures, such as components for propellers, impellers, and marine heat exchangers. However, in additive manufacturing, the high magnesium content of 5-series aluminum alloys presents significant challenges. Furthermore, hot cracking and the evaporation of strengthening elements lead to crack defects and poor densification in the resulting aluminum alloy composites. Summary of the Invention
[0005] The purpose of this invention is to provide a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, and an aluminum alloy composite material, to solve the technical problems in existing additive manufacturing processes. These problems stem from the high Mg content in 5-series aluminum alloys, which makes additive manufacturing difficult. Furthermore, the resulting aluminum alloy composite material suffers from crack defects and poor densification due to hot cracking and the evaporation of strengthening elements. Therefore, this invention achieves this through the following solution.
[0006] In a first aspect, the present invention provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, comprising: Obtain 5-series aluminum alloy powder, wherein the magnesium content of the 5-series aluminum alloy is 4-6 wt%; Titanium carbide particles and elemental powders are added to the 5-series aluminum alloy powder and mixed to make the titanium carbide particles uniformly dispersed on the surface of the 5-series aluminum alloy powder, thus obtaining a mixed powder. After the mixed powder is heat-treated, small-particle-size composite powder is collected by sieving; wherein the heat treatment temperature is 80~120℃ and the time is 2~8 hours, and the sieve mesh size is 150~200 mesh during the sieving process; The composite powder is additively formed to modify the 5-series aluminum alloy and obtain an aluminum alloy composite material.
[0007] Compared with existing technologies, the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders in this invention selects 5-series aluminum alloys with a magnesium content of 4-6 wt%. The mixed powder is obtained by dispersing titanium carbide particles on the surface of the 5-series aluminum alloy powder, i.e., by attaching titanium carbide particles to the surface of the 5-series aluminum alloy powder. Due to the good stability of titanium carbide particles, during additive forming (or additive manufacturing), the titanium carbide particles attached to the surface of the 5-series aluminum alloy powder can improve thermal diffusion between the composite powders and maintain the molten pool temperature at a stable value during additive forming (or additive manufacturing). This avoids excessive evaporation of Mg (magnesium) elements in the 5-series aluminum alloy powder, thus maintaining the original properties of the 5-series aluminum alloy while reducing the difficulty of additive manufacturing. Furthermore, the aforementioned titanium carbide particles possess advantages such as high hardness, high elastic modulus, and good thermal stability. After additive manufacturing, the strength of the prepared aluminum alloy composite material can be improved. Moreover, the lattice structure of the titanium carbide particles has a low mismatch with aluminum, allowing them to act as a grain refiner, eliminating the tendency for hot cracking during the printing process of the aluminum alloy composite material, and producing a dense, crack-free, fine-grained, and isotropic aluminum alloy composite material. In the above modification method, this invention adds elemental powder to the mixed powder. Selectively adding different types of elemental powder will bring different performance improvements to the aluminum alloy composite material. The type or amount of elemental powder can be selected according to the desired performance of the aluminum alloy composite material. For the modification of this 5-series aluminum alloy, adding elemental powder has the advantages of simplicity and economy. Through the above technical solution of this invention, the technical problems of existing additive manufacturing, such as the high Mg content in 5-series aluminum alloys, the difficulty of additive manufacturing, and the presence of crack defects and poor densification effect in the additive-manufactured aluminum alloy composite material due to hot cracking and the evaporation of strengthening elements, are solved.
[0008] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the 5-series aluminum alloys include 5083 aluminum alloy, 5056 aluminum alloy, 5154 aluminum alloy, and 5754 aluminum alloy and Al-Mg-Sc-Zr alloy; and / or, The particle size of the 5-series aluminum alloy powder is 10~60µm.
[0009] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the particle size of the titanium carbide particles is 50 nm to 5 µm; and / or, The proportion of titanium carbide particles in the mixed powder is 2-8 wt%.
[0010] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the elemental substance includes one or more of magnesium, manganese, copper, titanium, zinc and zirconium.
[0011] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the particle size of the elemental powder is 1~100µm; and / or, The proportion of elemental powder in the mixed powder is 0.5~8wt%.
[0012] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the additive forming of the composite powder includes: The composite powder is subjected to selective laser melting to complete additive manufacturing; The laser power is 200~400W, the scanning speed is 400~1200mm / s, and the layer thickness is 30~60µm.
[0013] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, during the selective laser melting of the composite powder, the oxygen content is less than 0.05% and the forming chamber pressure is 8~12 mbar.
[0014] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, the step of adding titanium carbide particles and elemental powders to the 5-series aluminum alloy powder for mixing includes: Titanium carbide particles and elemental powders were added to the 5-series aluminum alloy powder. By vibrating the powder, the titanium carbide particles are uniformly dispersed on the surface of the 5-series aluminum alloy powder.
[0015] Furthermore, in the method for modifying titanium carbide and elemental powders of 5-series aluminum alloys of the present invention, during the vibration mixing process, grinding balls with a particle size of 5-10 mm are used, the mass ratio of the mixture to the grinding balls is 1:(2-4), the vibration frequency is 40-60 Hz, and the vibration time is 1-4 hours.
[0016] Secondly, the present invention provides an aluminum alloy composite material, which is prepared by the above-mentioned titanium carbide and elemental powder modification method of 5-series aluminum alloy.
[0017] Compared with the prior art, the beneficial effects of the aluminum alloy composite material of the present invention are the same as those of the titanium carbide and element powder modification method of the 5-series aluminum alloy described in the above technical solution, and will not be repeated here. Attached Figure Description
[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to the present invention. Figure 2 This is a schematic diagram of the SEM morphology of the composite powder in Example 1 of the present invention; Figure 3 This is a schematic diagram of the energy spectrum of aluminum distribution in the composite powder of Example 1 of the present invention; Figure 4 This is a schematic diagram of the energy spectrum of magnesium element distribution in the composite powder of Example 1 of the present invention; Figure 5 This is a schematic diagram of the energy spectrum of titanium element distribution in the composite powder of Example 1 of the present invention; Figure 6 This is a schematic diagram of the horizontal microstructure of the 5083 aluminum alloy composite material in Example 1 of the present invention; Figure 7 This is a schematic diagram of the microstructure of the 5083 aluminum alloy composite material in Embodiment 1 of the present invention. Figure 8 This is a schematic diagram of the microstructure of the 5083 aluminum alloy composite material in Example 1; Figure 9 This is a schematic diagram of the energy spectrum of aluminum distribution in the 5083 aluminum alloy composite material of Example 1; Figure 10 This is a schematic diagram of the energy spectrum of magnesium distribution in the 5083 aluminum alloy composite material of Example 1; Figure 11 This is a schematic diagram of the energy spectrum of titanium distribution in the 5083 aluminum alloy composite material of Example 1; Figure 12 This is a schematic diagram of the IPF (Integrated Photopolymer Fiber) of the 5083 aluminum alloy composite material in Embodiment 1 of the present invention. Figure 13 This is a schematic diagram of the texture orientation and maximum texture index of the 5083 aluminum alloy composite material in Example 1 of the present invention; Figure 14 This is a schematic diagram of the grain size distribution of the 5083 aluminum alloy composite material in Embodiment 1 of the present invention; Figure 15This is a schematic diagram of the horizontal microstructure of the 5083 aluminum alloy composite material in Embodiment 2 of the present invention; Figure 16 This is a schematic diagram of the microstructure of the 5083 aluminum alloy composite material in Embodiment 2 of the present invention. Figure 17 This is a schematic diagram of the horizontal microstructure of the 5083 aluminum alloy composite material in Example 3 of the present invention; Figure 18 This is a schematic diagram of the microstructure of the 5083 aluminum alloy composite material in Embodiment 3 of the present invention. Figure 19 This is a schematic diagram of the horizontal microstructure of the 5083 aluminum alloy composite material in the comparative example of this invention; Figure 20 This is a schematic diagram of the microstructure of the 5083 aluminum alloy composite material in the comparative example of the present invention. Figure 21 This is a schematic diagram showing the mechanical properties of 5083 aluminum alloy composite materials containing different titanium carbides and elemental substances in this invention. Detailed Implementation
[0019] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.
[0020] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.
[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.
[0022] Selective laser melting (LPBF) is one of the most commonly used and effective additive manufacturing technologies for producing metal parts. It uses a computer-aided design model, where a high-energy laser beam melts the powder during the printing process, which then solidifies at an extremely rapid cooling rate. Employing a layer-by-layer melting and stacking method, it can produce customized parts with virtually unlimited design freedom. Since the component model comes from the computer design, this manufacturing technology eliminates the need for molds, shortening the production cycle and reducing material waste.
[0023] Aluminum alloys, as typical lightweight alloys, possess advantages such as low density, high specific strength, high thermal conductivity, and ease of processing. Commercially produced high-strength aluminum alloys are widely used in aerospace, marine, and automotive industries. 5-series aluminum alloys, with their excellent corrosion resistance, lack of low-temperature brittleness, and magnetism, are extensively used in ship hull structures, such as components for propellers, impellers, and marine heat exchangers. However, in additive manufacturing, the high magnesium content of 5-series aluminum alloys presents significant challenges. Furthermore, hot cracking and the evaporation of strengthening elements lead to crack defects and poor densification in the resulting aluminum alloy composites.
[0024] To address the aforementioned technical problems, in a first aspect, the present invention provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, comprising: Obtain 5-series aluminum alloy powder, wherein the magnesium content of the 5-series aluminum alloy is 4-6 wt%; Titanium carbide particles and elemental powders are added to the 5-series aluminum alloy powder and mixed to make the titanium carbide particles uniformly dispersed on the surface of the 5-series aluminum alloy powder, thus obtaining a mixed powder. After the mixed powder is heat-treated, small-particle-size composite powder is collected by sieving; wherein the heat treatment temperature is 80~120℃ and the time is 2~8 hours, and the sieve mesh size is 150~200 mesh during the sieving process; The composite powder is additively formed to modify the 5-series aluminum alloy and obtain an aluminum alloy composite material.
[0025] In the above-described technical solution, the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to the present invention selects 5-series aluminum alloys with a magnesium content of 4-6 wt%. The mixed powder is obtained by dispersing titanium carbide particles on the surface of the 5-series aluminum alloy powder, i.e., by attaching titanium carbide particles to the surface of the 5-series aluminum alloy powder. Due to the good stability of titanium carbide particles, during additive forming (or additive manufacturing), the titanium carbide particles attached to the surface of the 5-series aluminum alloy powder can improve the thermal diffusion between the composite powders and maintain the molten pool temperature at a stable value during additive forming (or additive manufacturing). This avoids excessive evaporation of Mg (magnesium) elements in the 5-series aluminum alloy powder, thus maintaining the original properties of the 5-series aluminum alloy while reducing the difficulty of additive manufacturing. Furthermore, the aforementioned titanium carbide particles possess advantages such as high hardness, high elastic modulus, and good thermal stability. After additive manufacturing, the strength of the prepared aluminum alloy composite material can be improved. Moreover, the lattice structure of the titanium carbide particles has a low mismatch with aluminum, allowing them to act as a grain refiner, eliminating the tendency for hot cracking during the printing process of the aluminum alloy composite material, and producing a dense, crack-free, fine-grained, and isotropic aluminum alloy composite material. In the above modification method, this invention adds elemental powder to the mixed powder. Selectively adding different types of elemental powder will bring different performance improvements to the aluminum alloy composite material. The type or amount of elemental powder can be selected according to the desired performance of the aluminum alloy composite material. For the modification of this 5-series aluminum alloy, adding elemental powder has the advantages of simplicity and economy. Through the above technical solution of this invention, the technical problems of existing additive manufacturing, such as the high Mg content in 5-series aluminum alloys, the difficulty of additive manufacturing, and the presence of crack defects and poor densification effect in the additive-manufactured aluminum alloy composite material due to hot cracking and the evaporation of strengthening elements, are solved.
[0026] Further, please refer to Figure 1 , Figure 1 This is a schematic diagram of a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to the present invention. Figure 1 The method involves first mixing 5083 aluminum alloy powder (particle size 15~53μm), TiC particles (particle size 50nm~5μm), and elemental powders Mg / Mn / Cu (particle size 5~100μm). The mixture is then uniformly dispersed using vibration mixing (frequency 60Hz, time 1~4h), followed by laser forming (i.e., additive manufacturing) to obtain a high-strength composite material (i.e., 5083 aluminum alloy composite material). It should be noted that the aluminum alloy used in this invention is not limited to 5-series aluminum alloys.
[0027] Furthermore, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, after the mixed powder is subjected to heat preservation treatment, the small-particle-size composite powder is collected by sieving. Heat preservation treatment can remove any moisture that may be present in the mixed powder, resulting in dry composite powder, thereby improving the efficiency of subsequent additive manufacturing. For example, the temperature of the heat preservation treatment can be 80°C, 100°C, or 120°C, the heat preservation treatment time can be 2 hours, 6 hours, or 8 hours, and the sieve mesh size during sieving is 150 mesh, 180 mesh, or 200 mesh.
[0028] It should be understood that in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, in order to further reduce the difficulty of powder spreading and additive forming (or additive manufacturing), it is also necessary to control the type of 5-series aluminum alloy in the above process and control the particle size of the 5-series aluminum alloy powder within a reasonable range; for example, the 5-series aluminum alloy includes 5083 aluminum alloy, 5056 aluminum alloy, 5154 aluminum alloy, 5754 aluminum alloy and Al-Mg-Sc-Zr alloy; the particle size of the 5-series aluminum alloy powder is 10~60µm; in another example, the 5-series aluminum alloy can be 5083 aluminum alloy, 5056 aluminum alloy, 5154 aluminum alloy, 5754 aluminum alloy or Al-Mg-Sc-Zr alloy, and the particle size of the 5-series aluminum alloy powder can be 10µm, 30µm, 50µm or 60µm.
[0029] It should be noted that the composition and content of each component of the above-mentioned different 5-series aluminum alloys are different. For example, in 5083 aluminum alloy, the content of silicon (Si) is 0.40 wt%, copper (Cu) is 0.10 wt%, magnesium (Mg) is 4.0~4.9 wt%, zinc (Zn) is 0.25 wt%, manganese (Mn) is 0.40~1.0 wt%, titanium (Ti) is 0.15 wt%, chromium (Cr) is 0.05~0.25 wt%, iron (Fe) is 0.00~0.40 wt%, and the balance is aluminum (Al). In 5056 aluminum alloy, the content of silicon (Si) is 0.30 wt%, iron (Fe) is 0.40 wt%, copper (Cu) is 0.10 wt%, manganese (Mn) is 0.05~0.20 wt%, chromium (Cr) is 0.05~0.200 wt%, magnesium (Mg) is 4.5~5.6 wt%, zinc (Zn) is 0.10 wt%, and the balance is aluminum (Al). In 5154 aluminum alloy, the content of silicon (Si) is ≤0.25 wt%, copper (Cu) is ≤0.10 wt%, magnesium (Mg) is 2.4~3.0 wt%, zinc (Zn) is ≤0.25 wt%, manganese (Mn) is 0.50~1.0 wt%, titanium (Ti) is ≤0.20 wt%, chromium (Cr) is 0.05~0.20 wt%, and iron (Fe) is 0.00~0.40 wt%. In the Al-Mg-Sc-Zr alloy, the magnesium (Mg) content is 4.2~5.1wt%, the scandium (Sc) content is 0.6~0.88wt%, the zirconium (Zr) content is 0.2~0.5wt%, the manganese (Mn) content is 0.3~0.8wt%, and the balance is aluminum (Al).
[0030] It should also be understood that in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders of the present invention, in order to further reduce the difficulty of powder spreading and additive forming (or additive manufacturing) and to make the prepared aluminum alloy composite material have high strength properties, it is also necessary to control the particle size of titanium carbide particles and ensure that the proportion of titanium carbide particles in the mixed powder is within a reasonable range; for example, the particle size of the titanium carbide particles is 50nm~5µm; the proportion of titanium carbide particles in the mixed powder is 2~8wt%; in another example, the particle size of the titanium carbide particles can be 50nm, 500nm, 1µm, 3µm or 5µm, and the proportion of titanium carbide particles in the mixed powder can be 2wt%, 4wt%, 6wt% or 8wt%.
[0031] As described above, this invention incorporates elemental powder into the mixed powder. Selectively adding different types of elemental powder will result in varying performance improvements in the aluminum alloy composite material. The type or amount of elemental powder can be selected based on the desired performance of the aluminum alloy composite material. For example, the elemental powder includes one or more of magnesium, manganese, copper, titanium, zinc, and zirconium. As another example, the elemental powder can be one or more of magnesium, manganese, copper, titanium, zinc, and zirconium. The particle size of the elemental powder can be 1~100µm; the proportion of elemental powder in the mixed powder can be 0.5~8wt%; for example, the particle size of the elemental powder can be 1µm, 30µm, 60µm, or 100µm, and the proportion of elemental powder in the mixed powder can be 0.5wt%, 1wt%, 4wt%, or 8wt%.
[0032] As one possible implementation, in the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to the present invention, the additive forming of the composite powder includes: The composite powder is subjected to selective laser melting to complete additive manufacturing; The laser power is 200~400W, the scanning speed is 400~1200mm / s, and the layer thickness is 30~60µm.
[0033] Using the above technical solution, selective laser melting can utilize computer-aided design models. During the forming (or printing) process, a high-energy laser beam melts the composite powder, which then solidifies at an extremely rapid cooling rate. Employing a layer-by-layer melting and stacking method, customized parts (or aluminum alloy composite materials) with virtually unlimited design freedom can be produced. Since the component model originates from computer design, this fabrication technology eliminates the need for molds, shortening the production cycle and reducing material waste. For example, during the selective laser melting of the composite powder, the laser power can be 200W, 300W, or 400W; the scanning speed can be 400mm / s, 600mm / s, 800mm / s, or 1200mm / s; and the layer thickness can be 30µm, 40µm, 50µm, or 60µm. Furthermore, during the selective laser melting of the composite powder, the oxygen content is less than 0.05%, and the forming chamber pressure is 8~12 mbar; for example, the oxygen content can be 0%, 0.02% or 0.03%, and the forming chamber pressure can be 8 mbar, 10 mbar or 12 mbar.
[0034] In one possible implementation, the method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to the present invention includes mixing titanium carbide particles and elemental powders into the 5-series aluminum alloy powder, comprising: Titanium carbide particles and elemental powders were added to the 5-series aluminum alloy powder. By vibrating the powder, the titanium carbide particles are uniformly dispersed on the surface of the 5-series aluminum alloy powder.
[0035] When using the above technical solution, vibration mixing can utilize the energy generated by mechanical vibration to uniformly disperse titanium carbide particles and elemental powder in 5-series aluminum alloy powder, and to uniformly disperse (or adhere) the titanium carbide particles on the surface of the 5-series aluminum alloy powder. This avoids the inability to additively form due to particle or powder aggregation, or the inhomogeneity of the properties of the aluminum alloy composite material obtained by additive forming. For example, in the vibration mixing process, grinding balls with a particle size of 5-10 mm are used, the mass ratio of the mixture to the grinding balls is 1:(2-4), the vibration frequency is 40-60 Hz, and the vibration time is 1-4 hours.
[0036] In another example, the particle size of the grinding balls can be 5 mm, 8 mm or 10 mm, the mass ratio of the mixture to the grinding balls can be 1:2, 1:3 or 1:4, the vibration frequency can be 40 Hz, 50 Hz or 60 Hz, and the vibration time can be 1 hour, 3 hours or 4 hours.
[0037] Secondly, the present invention provides an aluminum alloy composite material, which is prepared by the above-mentioned titanium carbide and elemental powder modification method of 5-series aluminum alloy.
[0038] With the above technical solution, the aluminum alloy composite material of the present invention is prepared by the titanium carbide and elemental powder modification method of the 5-series aluminum alloy described in the above technical solution. In this modification method, a 5-series aluminum alloy with a magnesium content of 4-6 wt% is selected, and titanium carbide particles are dispersed on the surface of the 5-series aluminum alloy powder, that is, titanium carbide particles are attached to the surface of the 5-series aluminum alloy powder to obtain the mixed powder. Due to the good stability of titanium carbide particles, during the additive forming (or additive manufacturing) process, the titanium carbide particles attached to the surface of the 5-series aluminum alloy powder can improve the thermal diffusion between the composite powders and maintain the molten pool temperature at a certain temperature value during the additive forming (or additive manufacturing) process. This can avoid excessive evaporation of Mg (magnesium) elements in the 5-series aluminum alloy powder, and while maintaining the original characteristics of the 5-series aluminum alloy, it improves the fluidity of the alloy powder, thereby reducing the difficulty of powder laying or additive manufacturing. Furthermore, titanium carbide particles possess advantages such as high hardness, high elastic modulus, and good thermal stability. After additive manufacturing, they can improve the strength of the prepared aluminum alloy composite material. Moreover, the lattice structure of titanium carbide particles has a low mismatch with aluminum, allowing them to act as a grain refiner, eliminating the tendency for hot cracking during the printing process of aluminum alloy composite materials, and producing a dense, crack-free, fine-grained, and isotropic aluminum alloy composite material. In the above modification method, this invention adds elemental powder to the mixed powder; selectively adding different types of elemental powder will bring different performance improvements to the aluminum alloy composite material.
[0039] To better understand the present invention, the following specific embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.
[0040] Unless otherwise specified, all raw materials used in the following examples are commercially available.
[0041] The following examples use a 5-series aluminum alloy (5083 aluminum alloy) as an example for detailed description. In the 5083 aluminum alloy used in the following examples and comparative examples, the content of silicon (Si) is 0.40 wt%, copper (Cu) is 0.10 wt%, magnesium (Mg) is 4.9 wt%, zinc (Zn) is 0.25 wt%, manganese (Mn) is 0.40 wt%, titanium (Ti) is 0.15 wt%, chromium (Cr) is 0.05 wt%, iron (Fe) is 0.40 wt%, and the balance is aluminum (Al). Example 1
[0042] This embodiment provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, including: S100 was used to obtain 5083 aluminum alloy powder with a particle size of 15~53µm; the magnesium content in this 5083 aluminum alloy was 4.9wt%. S200 involves adding 4 wt% titanium carbide (TiC) particles and 6 wt% metallic magnesium powder to 90 wt% 5083 aluminum alloy powder, and mixing them using a vibrating mixer to uniformly disperse the titanium carbide particles on the surface of the 5 series aluminum alloy powder, thus obtaining a mixed powder. The titanium carbide (TiC) particles have a particle size of 50 nm, and the magnesium powder has a particle size between 15 and 53 µm. The grinding balls of the vibrating mixer have a particle size of 10 mm, the mass ratio of the mixture to the grinding balls is 1:2, the vibration frequency of the vibrating mixer is 60 Hz, and the vibration time is 2 hours. S300: The mixed powder from step S200 is placed in an oven for heat preservation treatment, and then the small-particle-size composite powder is collected by sieving; wherein, the temperature of the oven during the heat preservation treatment is 120℃ and the heat preservation time is 4 hours; the sieve mesh size during the sieving process is 200 mesh; S400, the composite powder from step S300 is subjected to selective laser melting to complete the modification of the 5083 aluminum alloy and obtain the 5083 aluminum alloy composite material. The selective laser melting printing parameters are as follows: laser power 300W, scanning speed 800mm / s, layer thickness 30µm; oxygen content is less than 0.05% during the selective laser melting forming process, and the forming chamber pressure is maintained at 8~12mbar.
[0043] In this embodiment, after obtaining the composite powder in step S300, its morphology and elemental distribution are observed, such as... Figure 2 As shown, the 5083 aluminum alloy powder in this composite powder exhibits a certain degree of irregularity, but its particle size distribution meets the requirements of selective laser melting. Figures 3 to 5 It can be seen that the titanium carbide (TiC) particles are mainly attached to the surface of the 5083 aluminum alloy powder and are relatively uniform. The magnesium powder still maintains good sphericity and is uniformly dispersed in the 5083 aluminum alloy powder, which is conducive to improving the flowability of the composite powder and ensuring smooth powder spreading during selective laser melting.
[0044] The 5083 aluminum alloy composite material prepared in this embodiment was cut and separated, and its vertical and horizontal surfaces were ground to observe its microstructure. Figure 6 and Figure 7 As shown, after modification with TiC particles and elemental Mg powder, the 5083 aluminum alloy composite material exhibits no cracks on either the horizontal or vertical surfaces, and the number and size of defects such as pores and lack of fusion are effectively controlled. Please refer to [link / reference]. Figures 8 to 11In this 5083 aluminum alloy composite material, due to the influence of factors such as laser recoil pressure, Marangoni convection, and gravity during the printing process, the nano-sized TiC particles have small mass and form particle agglomerates of a certain size under stress, but the overall distribution is uniform. The Mg elemental powder is completely melted and can still diffuse fully under extremely rapid cooling rates. The Mg element is uniformly distributed in the printed sample, with no elemental segregation. Please refer to [link / reference]. Figures 12 to 14 , Figure 12 This is a schematic diagram (pole diagram) of the straight-plane IPF of the 5083 aluminum alloy composite material in this embodiment. Figure 13 This is a schematic diagram of the texture orientation and maximum texture index of the 5083 aluminum alloy composite material in this embodiment; Figure 14 This is a schematic diagram of the grain size distribution of the 5083 aluminum alloy composite material in Example 1. Figure 12 It can be seen that the grain structure of the 5083 aluminum alloy composite material in this embodiment is a completely equiaxed crystalline region, and the grains exhibit submicron-sized grains without preferred orientation. Figure 13 It can be seen that in this embodiment, the 5083 aluminum alloy composite material exhibits equiaxed, non-textured grain orientation, with a maximum texture index of only 1.66, indicating that the fine grains are randomly oriented. Figure 14 As can be seen, most of the grains in the aluminum alloy composite material of this embodiment are about 1.5 micrometers in size, with little difference in grain size and an average grain size of 1.74 micrometers, showing a significant grain refinement effect. Example 2
[0045] This embodiment provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, including: S100 was used to obtain 5083 aluminum alloy powder with a particle size of 15~53µm, and the magnesium content in the 5083 aluminum alloy was 4.9wt%. S200 involves adding 4 wt% titanium carbide (TiC) particles and 2 wt% metallic manganese (Mn) powder to 94 wt% 5083 aluminum alloy powder, and mixing them using a vibrating powder mixer to uniformly disperse the titanium carbide particles on the surface of the 5 series aluminum alloy powder, thus obtaining a mixed powder. The titanium carbide (TiC) particles have a particle size of 50 nm, and the manganese (Mn) powder has a particle size of 20 µm. The grinding balls of the vibrating mixer have a particle size of 5 mm, the mass ratio of the mixture to the grinding balls is 1:4, the vibration frequency of the vibrating mixer is 60 Hz, and the vibration time is 4 hours. S300: The mixed powder from step S200 is placed in an oven for heat preservation treatment, and then the small-particle-size composite powder is collected by sieving; wherein, the temperature of the oven during the heat preservation treatment is 120℃ and the heat preservation time is 4 hours; the sieve mesh size during the sieving process is 200 mesh; S400, the composite powder from step S300 is subjected to selective laser melting to complete the modification of the 5083 aluminum alloy and obtain the 5083 aluminum alloy composite material. The selective laser melting printing parameters are as follows: laser power 300W, scanning speed 800mm / s, layer thickness 30µm; oxygen content is less than 0.05% during the selective laser melting forming process, and the forming chamber pressure is maintained at 8~12mbar.
[0046] In this embodiment, after preparing the above-mentioned 5083 aluminum alloy composite material, its microstructure was observed. Please refer to 15 and... Figure 16 In this embodiment, no cracks were found on different construction surfaces of the 5083 aluminum alloy composite material, indicating a good densification effect. Combining Embodiments 1 and 2, it can be shown that TiC particles of different sizes can effectively suppress the generation of hot cracks in easily crackable aluminum alloys, and the addition of elemental powders of different types, sizes, and mass proportions does not affect the molding effect of the aluminum alloy composite material. Example 3
[0047] This embodiment provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, including: S100 was used to obtain 5083 aluminum alloy powder with a particle size of 15~53µm, and the magnesium content in the 5083 aluminum alloy was 4.9wt%. S200 involves adding 4 wt% titanium carbide (TiC) particles and 4 wt% magnesium (Mg) powder to 92 wt% 5083 aluminum alloy powder, and mixing them using a vibrating mixer to uniformly disperse the titanium carbide particles on the surface of the 5 series aluminum alloy powder, thus obtaining a mixed powder. The titanium carbide (TiC) particles have a particle size of 5µm, and the magnesium (Mg) powder has a particle size of 100µm; the grinding balls of the vibrating mixer have a particle size of 5mm, the mass ratio of the mixture to the grinding balls is 1:3, the vibration frequency of the vibrating mixer is 60Hz, and the vibration time is 4 hours. S300: The mixed powder from step S200 is placed in an oven for heat preservation treatment, and then the small-particle-size composite powder is collected by sieving; wherein, the temperature of the oven during the heat preservation treatment is 80℃ and the heat preservation time is 8 hours; the sieve mesh size during the sieving process is 150 mesh. S400, the composite powder from step S300 is subjected to selective laser melting to complete the modification of the 5083 aluminum alloy and obtain the 5083 aluminum alloy composite material. The selective laser melting printing parameters are as follows: laser power 200W, scanning speed 1200mm / s, layer thickness 60µm; oxygen content is less than 0.05% during the selective laser melting forming process, and the forming chamber pressure is maintained at 8~12mbar.
[0048] This embodiment observes the microstructure of the 5083 aluminum alloy composite material after its preparation. Please refer to [link to relevant documentation]. Figure 17 and Figure 18 Similar to Examples 1 and 2 above, the 5083 aluminum alloy composite material in this example has no cracks on different construction surfaces and has a good densification effect. Example 4
[0049] This embodiment provides a method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, including: S100 was used to obtain 5083 aluminum alloy powder with a particle size of 15~53µm, and the magnesium content in the 5083 aluminum alloy was 4.9wt%. S200 involves adding 8 wt% titanium carbide (TiC) particles and 8 wt% metallic manganese (Mn) powder to 84 wt% of 5083 aluminum alloy powder, and mixing them using a vibrating powder mixer to uniformly disperse the titanium carbide particles on the surface of the 5 series aluminum alloy powder, thereby obtaining a mixed powder. The titanium carbide (TiC) particles have a particle size of 3~5µm, and the manganese (Mn) powder has a particle size of 15~53µm; the grinding balls of the vibrating mixer have a particle size of 5mm, the mass ratio of the mixture to the grinding balls is 1:3, the vibration frequency of the vibrating mixer is 60Hz, and the vibration time is 4 hours. S300: The mixed powder from step S200 is placed in an oven for heat preservation treatment, and then the small-particle-size composite powder is collected by sieving; wherein, the temperature of the oven during the heat preservation treatment is 80℃ and the heat preservation time is 8 hours; the sieve mesh size during the sieving process is 150 mesh. S400, the composite powder from step S300 is subjected to selective laser melting to complete the modification of the 5083 aluminum alloy and obtain the 5083 aluminum alloy composite material. The selective laser melting printing parameters are as follows: laser power 200W, scanning speed 1200mm / s, layer thickness 60µm; oxygen content is less than 0.05% during the selective laser melting forming process, and the forming chamber pressure is maintained at 8~12mbar.
[0050] In this embodiment, after the 5083 aluminum alloy composite material was prepared, its microstructure was observed. No cracks were found on different construction surfaces of the 5083 aluminum alloy composite material in this embodiment, and the densification effect was good, which is basically the same as that of Examples 1 to 3 above.
[0051] Comparative Example This comparative example provides a method for modifying 5-series aluminum alloys. Compared with Example 2, it does not include titanium carbide (TiC) particles or elemental powder (manganese powder in Example 2). The modification method includes: S100 involves placing 5083 aluminum alloy powder with a particle size of 15~53µm in an oven for heat preservation treatment, and then collecting the small-particle-size aluminum alloy powder by sieving. During the heat preservation treatment, the temperature of the oven is 120℃ and the heat preservation time is 4 hours. During the sieving process, the screen mesh size is 200 mesh. S200, selective laser melting and forming of aluminum alloy powder after heat preservation and sieving in step S100 to obtain 5083 aluminum alloy composite material. The selective laser melting printing parameters are as follows: laser power 300W, scanning speed 800mm / s, layer thickness 30µm; oxygen content is less than 0.05% during the selective laser melting forming process, and the forming chamber pressure is maintained at 8~12mbar.
[0052] It should be noted that 5083 aluminum alloy is a crack-prone alloy. During the selective laser melting (or selective laser melting printing) process in this comparative example, severe powder splashing and solute segregation occurred, resulting in a large number of pores and incomplete fusion defects in the obtained 5083 aluminum alloy composite material. For detailed microstructure, please refer to [link to relevant documentation]. Figure 19 and Figure 20 Furthermore, in this 5083 aluminum alloy composite material, fewer crystal nuclei grow along the temperature gradient direction inside the molten pool and eventually form coarse columnar crystals. Since there is no possible filling phase between the crystals, a large number of hot cracks that are consistent with the growth direction of the columnar crystals often form between the columnar crystals.
[0053] Please see Figure 21 , Figure 21 The results show that 5083 aluminum alloy composites obtained by adding TiC particles of different sizes and mass ratios, as well as elemental powders of different types, particle sizes and mass ratios, exhibit different mechanical properties. Figure 21 There are multiple curves, among which the curve corresponding to "5083 powder printing state" is the mechanical property curve of the 5083 aluminum alloy composite material obtained in the above comparative example, indicating that no TiC or elemental substances were added to the 5083 aluminum alloy composite material; "4TiC" 50nm +6Mg 15-53μm The curve corresponding to " / 5083 composite powder printing state" is the mechanical property curve of the 5083 aluminum alloy composite material obtained in Example 1 above, indicating that 4 wt% TiC particles and 6 wt% metallic Mg powder were added to the 5083 aluminum alloy powder; "4TiC 50nm +2Mn 20μm The curve corresponding to " / 5083 composite powder printing state" is the mechanical property curve of the 5083 aluminum alloy composite material obtained in Example 2 above, indicating that 4 wt% TiC particles and 2 wt% metallic Mn powder were added to the 5083 aluminum alloy powder. The meanings of the remaining curves are the same as the three curves mentioned above. Figure 21 It can be concluded that, corresponding to the above comparative examples, the 5083 aluminum alloy composite material in the "5083 composite powder printing state" exhibits numerous defects such as cracks and pores, completely lacking mechanical properties. Conversely, the curves corresponding to Examples 1 and 2, as well as other curves, show that adding TiC and / or elemental substances to the 5083 aluminum alloy powder results in additively formed 5083 aluminum alloy composite materials exhibiting different mechanical properties. This demonstrates that, based on using TiC particles of different sizes as the core to ensure the printability (or additive formability) of 5-series aluminum alloys, further simple addition of elemental powders can effectively control the mechanical properties of the material. In practice, the technical solution of this invention can prepare high-strength aluminum alloy composite materials that meet different application environment conditions.
[0054] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.
[0055] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A method for modifying 5-series aluminum alloys with titanium carbide and elemental powders, characterized in that, include: Obtain 5-series aluminum alloy powder, wherein the magnesium content in the 5-series aluminum alloy is 4-6 wt%; the 5-series aluminum alloy is 5083 aluminum alloy. The particle size of the 5-series aluminum alloy powder is 10~60µm; Titanium carbide particles and elemental powder are added to the 5-series aluminum alloy powder and mixed. Grinding balls with a particle size of 5-10 mm are used, the mass ratio of the mixture to the grinding balls is 1:(2-4), the vibration frequency is 40-60 Hz, and the vibration time is 1-4 hours. The titanium carbide particles are uniformly dispersed on the surface of the 5-series aluminum alloy powder to obtain a mixed powder. The elemental powder is magnesium and / or manganese. After the mixed powder is heat-treated, small-particle-size composite powder is collected by sieving; wherein the heat treatment temperature is 80~120℃ and the time is 2~8 hours, and the sieve mesh size is 150~200 mesh during the sieving process; The composite powder is subjected to selective laser melting to complete additive manufacturing, thereby modifying the 5-series aluminum alloy and obtaining an aluminum alloy composite material; wherein the laser power is 200~400W, the scanning speed is 400~1200mm / s, and the layer thickness is 30~60µm. The titanium carbide particles have a particle size of 50 nm to 5 µm, and the proportion of titanium carbide particles in the mixed powder is 2 to 8 wt%; the particle size of the elemental powder is 1 to 100 µm; the proportion of elemental powder in the mixed powder is 0.5 to 8 wt%; during the selective laser melting of the composite powder, the oxygen content is less than 0.05%, and the forming chamber pressure is 8 to 12 mbar.
2. The method for modifying 5-series aluminum alloys with titanium carbide and elemental powders according to claim 1, characterized in that, The process of adding titanium carbide particles and elemental powder to the 5-series aluminum alloy powder and mixing them includes: Titanium carbide particles and elemental powders were added to the 5-series aluminum alloy powder. By vibrating the powder, the titanium carbide particles are uniformly dispersed on the surface of the 5-series aluminum alloy powder.
3. An aluminum alloy composite material, characterized in that, It is prepared using the titanium carbide and elemental powder modification method of the 5-series aluminum alloy as described in claim 1 or 2.