A method for additive manufacturing of a titanium alloy material having high strength and high wear resistance

Abstract

The application relates to a method for manufacturing a high-strength and high-wear-resistance additive manufacturing titanium alloy material, and belongs to the field of titanium alloy manufacturing. The application is based on powder composition design and 3D printing process to manufacture a high-strength and high-wear-resistance titanium alloy, and laser selective melting process is adopted during printing; Si, Cr, Fe and Al elements are added in titanium, and the proportion range of Si and Cr is controlled, about 22wt% of Ti5Si3 phases are formed in a beta titanium matrix, the Ti5Si3 phases are discontinuously distributed in the Ti matrix in a network shape, in addition, 12wt% of Ti3Al phases and 7wt% of Ti 33.5 Al 32.71 Cr 27.6 Fe 6.19 phases are dispersedly distributed in the matrix, and the sizes of the two phases are 3-5 microns; the discontinuously network-shaped distributed Ti5Si3 phases and the dispersedly distributed Ti3Al phases and Ti 33.5 Al 32.71 Cr 27.6 Fe 6.19 phases all have high hardness and wear resistance, can greatly improve the strength and wear resistance of the titanium alloy, the wear resistance is more than 3 times that of ordinary TC4 titanium alloy under the same condition, and the tensile strength is more than 1350MPa.

Description

Technical Field

[0001] This invention belongs to the field of metallic materials and relates to a method for manufacturing titanium alloy materials. Background Technology

[0002] Titanium alloys possess excellent comprehensive properties such as low density, high specific strength, high temperature resistance, and corrosion resistance, making them one of the most important structural materials for aircraft fuselages and aero engines. With the development of titanium alloy technology, they are also widely used in other fields, where the operating environments are becoming increasingly complex, and the requirements for their comprehensive performance are becoming increasingly stringent. However, titanium alloys have drawbacks such as low surface hardness, poor wear resistance, and susceptibility to high-temperature oxidation, which seriously affect the safety and reliability of their structures and limit their application in friction mechanisms. Therefore, improving the surface properties of titanium alloys, such as hardness, wear resistance, and high-temperature oxidation resistance, has become an urgent problem to be solved in order to broaden their application range.

[0003] Improving the wear resistance of metallic materials typically involves designing alloy compositions to increase hardness, thereby enhancing wear resistance. However, for titanium alloys, increasing hardness means greater difficulty in subsequent machining. Therefore, traditional titanium alloys, considering machinability, must also take this into account during composition design. This results in traditional titanium alloys possessing excellent mechanical properties and machinability, but with relatively low hardness and poor wear resistance, making them unsuitable for applications requiring a balance between mechanical properties and wear resistance. The rapidly developing additive manufacturing (i.e., 3D printing) technology in recent years allows for the direct forming of samples of various shapes without shape limitations. After forming, no further processing is needed, making the manufacture of high-strength, high-wear-resistant titanium alloys possible. Although extensive research has been conducted both domestically and internationally on additive manufacturing of titanium alloys, most studies are based on conventional grades, such as TC4 alloy, lacking mature titanium alloy grades that combine both wear resistance and good mechanical properties. Therefore, developing a titanium alloy suitable for 3D printing that balances wear resistance and mechanical properties has become a pressing need. Summary of the Invention

[0004] This invention, through alloy composition design, forms a variety of high-hardness, dispersed reinforcing phases in the titanium matrix. These reinforcing phases interact with each other, giving the titanium alloy excellent mechanical properties and wear resistance. Its tensile strength exceeds 1350 MPa, and its wear resistance is more than three times that of conventional TC4 alloy.

[0005] A method for additive manufacturing titanium alloy materials with high strength and high wear resistance is disclosed. This method utilizes powder composition design and 3D printing technology to manufacture high-strength, high-wear-resistant titanium alloys, employing a laser selective melting process during printing. By adding Si, Cr, Fe, and Al elements to titanium and controlling the ratio of Si and Cr, approximately 22 wt% of a Ti5Si3 phase is formed in a β-titanium matrix, which is distributed in a discontinuous network within the Ti matrix. Additionally, approximately 12 wt% of a Ti3Al phase and approximately 7 wt% of Ti are dispersed within the matrix. 33.5 Al 32.71 Cr 27.6 Fe 6.19 The two phases have a size of 3–5 micrometers; thus, there is a discontinuous network distribution of Ti5Si3 phase and a dispersed distribution of Ti3Al phase and Ti 33.5 Al 32.71 Cr 27.6 Fe 6.19 The phase has high hardness and wear resistance, which can significantly improve the strength and wear resistance of titanium alloys. Under the same conditions, its wear resistance is more than 3 times that of ordinary TC4 titanium alloy, while its tensile strength exceeds 1350MPa.

[0006] The method for additive manufacturing titanium alloy materials with high strength and high wear resistance as described above includes the following specific preparation steps:

[0007] 1) Raw material powder is prepared by gas atomization powder preparation technology. The powder composition mass ratio is Al: 20-22 wt%, Fe: 10-11 wt%, Si: 5-6 wt%, Cr: 5-6 wt%, Si:Cr ratio is 1:1, and the balance is Ti and unavoidable impurities. The particle size of the powder is controlled in the range of 10-80 μm.

[0008] 2) The process parameters for laser selective melting printing are as follows: laser power 150-250W, scanning speed 700-1500mm / s, spot diameter 0.060-0.065mm, scanning spacing 0.100~0.150mm, powder layer thickness 0.030~0.035mm, substrate temperature 50~80℃, and argon atmosphere protection during the printing process.

[0009] The advantage of this invention is that the titanium alloy prepared by selective laser melting and using the above-mentioned composition and process not only prints without cracks, but also has high tensile strength and wear resistance. Its tensile strength exceeds 1350MPa and its wear resistance is more than 3 times that of conventional TC4 alloy.

[0010] The main mechanism of the alloy composition design in this invention is as follows: By adding Si, Cr, Fe, and Al elements to titanium and controlling the ratio range of Si and Cr, approximately 22 wt% of Ti5Si3 phase can be formed in the β-titanium matrix. This phase is distributed in a discontinuous network within the Ti matrix. Additionally, 12 wt% of Ti3Al phase and approximately 7 wt% of Ti are dispersed in the matrix. 33.5 Al 32.71 Cr 27.6 Fe 6.19 The two phases have a size of approximately 3–5 micrometers. This includes a discontinuous network distribution of the Ti5Si3 phase and a dispersed distribution of the Ti3Al and Ti... 33.5 Al 32.71 Cr 27.6 Fe 6.19 The phase has high hardness and wear resistance, which can significantly improve the strength and wear resistance of titanium alloys. Under the same conditions, its wear resistance is more than 3 times that of ordinary TC4 titanium alloy, while its tensile strength exceeds 1350MPa. Detailed Implementation

[0011] Example 1

[0012] Titanium alloy materials with tensile strength of 1350–1380 MPa prepared by selective laser melting.

[0013] 1) The raw material powder was prepared by gas atomization powder preparation technology. The powder composition mass ratio was Al: 20wt%, Fe: 10wt%, Si: 5wt%, Cr: 5wt%, with the Si:Cr ratio being 1:1. The balance was Ti and unavoidable impurities. The particle size of the powder was controlled within the range of 10-80μm.

[0014] 2) The process parameters for laser selective melting printing are as follows: laser power 150W, scanning speed 700mm / s, spot diameter 0.060mm, scanning spacing 0.100mm, powder layer thickness 0.030mm, substrate temperature 50℃, and argon atmosphere protection during the printing process.

[0015] Performance tests showed that the material has a tensile strength of 1370 MPa and wear resistance that is 3.5 times that of TC4 alloy.

[0016] Example 2

[0017] Preparation of titanium alloy materials with tensile strength of 1380-1400 MPa

[0018] 1) The raw material powder was prepared by gas atomization powder preparation technology. The powder composition mass ratio was Al: 22wt%, Fe: 11wt%, Si: 6wt%, Cr: 6wt%, with the Si:Cr ratio being 1:1. The balance was Ti and unavoidable impurities. The particle size of the powder was controlled within the range of 10-80μm.

[0019] 2) The process parameters for printing using laser selective melting are as follows: laser power 250W, scanning speed 1500mm / s, spot diameter 0.065mm, scanning spacing 0.150mm, powder layer thickness 0.035mm, substrate temperature 80℃, and argon atmosphere protection during the printing process.

[0020] Performance tests showed that the material has a tensile strength of 1392 MPa and a wear resistance four times that of TC4 alloy.

Claims

1. A method for additive manufacturing titanium alloy materials with high strength and high wear resistance, characterized in that, High-strength, high-wear-resistant titanium alloys are manufactured using powder composition design and 3D printing technology, employing laser selective melting during printing. By adding Si, Cr, Fe, and Al elements to titanium and controlling the ratio of Si and Cr, a 22wt% Ti5Si3 phase is formed in the β-titanium matrix, which is distributed in a discontinuous network within the Ti matrix. Additionally, 12wt% Ti3Al phase and 7wt% Ti are dispersedly distributed in the matrix. 33.5 Al 32.71 Cr 27.6 Fe 6.19 The two phases have a size of 3–5 micrometers; thus, there is a discontinuous network distribution of Ti5Si3 phase and a dispersed distribution of Ti3Al phase and Ti 33.5 Al 32.71 Cr 27.6 Fe 6.19 The phase has high hardness and wear resistance, which can significantly improve the strength and wear resistance of titanium alloys. Under the same conditions, its wear resistance is more than 3 times that of ordinary TC4 titanium alloy, while its tensile strength exceeds 1350MPa. The specific preparation steps are as follows: 1) Raw material powder is prepared by gas atomization powder preparation technology. The powder composition mass ratio is Al: 20-22 wt%, Fe: 10-11 wt%, Si: 5-6 wt%, Cr: 5-6 wt%, Si:Cr ratio is 1:1, and the balance is Ti and unavoidable impurities. The particle size of the powder is controlled in the range of 10-80 μm. 2) The process parameters for laser selective melting printing are as follows: laser power 150-250W, scanning speed 700-1500mm / s, spot diameter 0.060-0.065mm, scanning spacing 0.100~0.150mm, powder layer thickness 0.030~0.035mm, substrate temperature 50~80℃, and argon atmosphere protection during the printing process.