氧含量对热等静压TC4钛合金力学性能的影响

Effect of oxygen content on mechanical properties of hot isostatic pressing TC4 titanium alloy

本文对热等静压工艺制备的TC4粉末钛合金材料进行力学性能、微观组织及断口对比分析,研究氧含量对其力学性能的影响。结果表明:热等静压态和退火态的TC4钛合金显微组织无明显差异,均为片层状组织;氧含量由0.11%上升至0.17%,钛合金强度明显提高,塑性略有下降,TC4钛合金的断裂韧度KIC由101 MPa·m1/2下降到95 MPa·m1/2;TC4钛合金的室温拉伸的断裂机制是典型的微孔聚集型断裂机制,随氧含量的增加韧性断面上出现解理小面。

In this paper,the mechanical properties,microstructures and fracture surfaces of TC4 powder titanium alloy prepared by hot isostatic pressing were compared and analyzed,and the effect of oxygen content on its mechanical properties was studied.The results show that the microstructures of TC4 titanium alloys as hot isostatic pressing and annealing have no obvious difference and are lamellar;the oxygen content increases from 0.11%to0.17%,the strength and plasticity of titanium alloys increase obviously,and the fracture toughness KICof TC4 titanium alloys decreases from 101 MPa·m1/2 to 95 MPa·m1/2;the fracture mechanism of TC4 titanium alloys under room temperature tension is typical microporous aggregation fracture.The mechanism is that cleavage facets appear on the tough section with the increase of oxygen content.