摘要
Ti-6 Al-4 V alloy powder was processed by electrode induction melting gas atomization(EIGA)at high gas pressure(5.5-7.0 MPa).The effects of atomizing gas pressure on the powder characteristics and the microstructure,along with the mechanical properties of the as-fabricated block by laser melting deposition(LMD),were investigated.The results indicate that the diameters of powders are distributed in a wide range of sizes from 1 to 400μm,and the median powder size(d50)decreases with increasing gas pressure.The powders with a size fraction of 100-150μm obtained at gas pressures of 6.0 and 6.5 MPa have better flowability.The oxygen content is consistent with the change trend of gas pressure within a low range of 0.06%-0.20%.Specimens fabricated by LMD are mainly composed ofα+βgrains with a fine lamellar Widmanstatten structures and have the ultimate tensile strength(UTS)and yield strength of approximately 1100 and 1000 MPa,respectively.Furthermore,the atomized powders have a favorable 3 D printing capability,and the mechanical properties of Ti-6 Al-4 V alloys manufactured by LMD typically exceed those of their cast or wrought counterparts.
采用电极感应熔炼气雾化(EIGA)设备制备Ti-6Al-4V合金粉末,研究高压(5.5~7.0 MPa)雾化压力对粉末特性和显微结构的影响,并分析激光打印(LMD)件的力学性能。结果表明:所制备的粉末粒径分布在1~400μm,随着雾化压力的增加,粉末的平均粒径逐渐减小。在气压6.0和6.5 MPa下制备的粒径分布在100~150μm范围内的粉末具有较好的流动性。粉末的氧含量随着压力的升高而增加,但均在0.06%~0.20%较低范围内。LMD制备的TC4试样主要由具有魏氏结构的α和β两相组成,其极限抗拉强度和屈服强度分别约为1100 MPa和1000 MPa。EIGA法制备的钛合金粉末具有良好的3D可打印性,LMD制备的TC4合金的力学性能超过铸造或锻造件的。
基金
Project(2017YFB0305801)supported by the National Key R&D Program of China
Project(U1508213)supported by the Joint-Fund of NSFC-Liaoning,China
Project(51771051)supported by the National Natural Science Foundation of China.
作者简介
Corresponding author:Chang-sheng LIU,Tel:+86-24-83687575,E-mail:csliu@mail.neu.edu.cn
