US 12,280,426 B2
Si-containing high-strength and low-modulus medical titanium alloy, and additive manufacturing method and use thereof
Yuanyuan Li, Guangzhou (CN); Chao Yang, Guangzhou (CN); Xuan Luo, Guangzhou (CN); Dongdong Li, Changchun (CN); Yanguo Qin, Changchun (CN); and Ning Li, Wuhan (CN)
Assigned to South China University of Technology, Guangzhou (CN)
Appl. No. 17/768,925
Filed by South China University of Technology, Guangzhou (CN); Huazhong University of Technology, Wuhan (CN); and Jilin University, Changchun (CN)
PCT Filed Oct. 29, 2020, PCT No. PCT/CN2020/124598
§ 371(c)(1), (2) Date Apr. 14, 2022,
PCT Pub. No. WO2021/139334, PCT Pub. Date Jul. 15, 2021.
Claims priority of application No. 202010009147.2 (CN), filed on Jan. 6, 2020.
Prior Publication US 2024/0100598 A1, Mar. 28, 2024
Int. Cl. B22F 10/28 (2021.01); B22F 9/08 (2006.01); B22F 10/32 (2021.01); B22F 10/36 (2021.01); B22F 10/366 (2021.01); B22F 10/38 (2021.01); B22F 12/17 (2021.01)
CPC B22F 10/28 (2021.01) [B22F 9/08 (2013.01); B22F 10/36 (2021.01); B22F 10/366 (2021.01); B22F 12/17 (2021.01); B22F 2009/0808 (2013.01); B22F 10/32 (2021.01); B22F 10/38 (2021.01); B22F 2301/205 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An additive manufacturing method of a Si-containing high-strength and low-modulus medical titanium alloy, characterized by comprising the following steps:
(1) Alloy Ingredient Design: 0.1-5 at. % bioactive element Si is added into a low elastic modulus TiNbTaZr-based alloy, then according to the d-electron theory, the average number of bonding times of the alloy Bo is calculated by

OG Complex Work Unit Math
 wherein (Bo)i is the covalent bond energy determined by the d electronic cloud overlapping between the alloy element i and the matrix alloy element; the average d electron orbital energy level of the alloy Md is calculated by

OG Complex Work Unit Math
 wherein (Md), is the average value of the M−d energy level of the alloy element i, i is the alloy element Nb and Ta, Xi is the atomic percentage of the alloy element i; according to a β-Ti region of a Bo−Md relationship graph, the calculated values of Bo and Md are selected to fall in a meta-stable β-Ti region of the Bo−Md relationship graph; then according to a Ti—Zr—Si ternary phase graph, the alloy ingredient range which is deviated from the eutectic point and close to the maximum solid solubility of Si in Ti is selected, so that the alloy ingredients of the Si-containing high-strength and low-modulus medical titanium alloy are formulated in the ingredient proportion of Ti 60-70 at. %, Nb 16-24 at. %, Zr 4-14 at. %, Ta 1-8 at. %, Si 0.1-5 at. %, by using sponge titanium, sponge zirconium, tantalum niobium intermediate alloy, and elemental silicon, as raw materials;
(2) Powder Preparation: the elements Ti, Nb, Zr, Ta and Si are compounded according to the contents of step (1), melted by a Vacuum Arc Remelting furnace so as to prepare an alloy rod, the titanium alloy powders are prepared by Electrode Induction Melting Gas Atomization method (EIGA) or Plasma Rotating Electrode Processing method (PREP), and sieved so as to obtain spherical powders having the range of particle sizes suitable for the additive manufacturing;
(3) Model construction and substrate preheating: the three-dimensional model of the structural parts to be prepared is constructed, slicing is completed and print files are created, the preheating temperature of the substrate in Selective Laser Melting is 150-650° C., and the preheating temperature of the substrate in Selective Electron Beam Melting is 650-1200° C.;
(4) Additive manufacturing molding: the additive manufacturing molding is carried out by a Selective Laser Melting apparatus or a Selective Electron Beam Melting apparatus so as to obtain a high-strength and low-modulus medical titanium alloy; wherein the key molding parameters are: 50%≤melting channel overlapping rate μ≤80%, 1000 mm/s≤scanning speed V≤10000 mm/s; in the case of the Selective Laser Melting, the laser input power P is 140 W≤P≤360 W, the laser scanning pitch h is 20-80 μm, and in the case of the Selective Electron Beam Melting, the electron gun current I is 8 mA≤1≤100 mA and the electron beam scanning pitch h is 20-200 μm.