退火温度对激光选区熔化成形TC4合金显微组织和力学性能的影响

Effects of Annealing Temperature on Microstructure and Mechanical Properites of TC4 Alloy Prepared by Selective Laser Melting

研究了退火温度对激光选区熔化成形TC4合金显微组织和力学性能的影响规律。结果表明,激光选区熔化成形TC4合金由β柱状晶和晶内析出的弥散分布的针状马氏体α'相组成,在700℃以上退火处理,马氏体α'相先分解成α+β相。随着退火温度的升高,钛合金构件显微硬度和抗拉强度逐渐降低,伸长率逐渐升高。经过800℃退火处理之后,材料的伸长率为9.79%,抗拉强度为1146 MPa,完全满足航空标准需求。

The influence of annealing temperature on the microstructure and mechanical properties of TC4 alloy prepared by selective laser melting was studied.The experimental results show that this experimental TC4 alloy is composed of primaryβcolumnar grains and diffusion-distributed acicular martensiteα'phase precipitated in crystal.When the annealing temperature above 700℃,martensiticα'phase is decomposed intoα+βphase.With the increase of annealing temperature,the microhardness and tensile strength of TC4 alloy decrease,but the elongation increases.After annealing at 800℃,the elongation of this experimental TC4 alloy is 9.79%and the tensile strength is 1146 MPa,which fully meets the requirements of aviation standards.