烧结温度对内燃机用TiZrVMo高熔合金组织和力学性能的影响

运用放电等离子烧结方法(SPS)制备TiZrVMo合金,并通过控制不同的烧结温度获得了不同力学特性与组织结构的试样。测试结果表明,对合金烧结处理后其基体中形成了包含BCC与FCC两种晶体结构,BCC组织形成了比FCC组织更高的衍射峰。当烧结温度增加后,晶粒尺寸呈现增大的现象,塑性先增大后降低。经过1100℃烧结得到的试样压缩屈服强度为1501.4MPa,塑性应变31.4%。随着烧结温度的增加,屈服强度先减少后增加,塑性应变先增大后减小。当烧结温度上升后,合金材料从准脆性断裂逐渐转变为微孔聚集型断裂,之后形成了大尺寸晶粒并发生沿晶断裂的现象,呈现脆性解理断裂的特点。

Effect of Sintering Temperature on Microstructure and Mechanical Properties of TiZrVMo Alloy Used for Internal Combustion Engine

TiZrVMo alloy was prepared by electric spark plasma sintering(SPS),and samples with different mechanical properties and microstructure were obtained by controlling different sintering temperatures.The results show that two crystal structures including BCC and FCC are formed in alloy matrix after sintering,and diffraction peak of BCC is higher than that of FCC.Upon increase of sintering temperature,grain size rises and plasticity rises first and drops later.The sample sintered at 1100℃has compressive yield strength of 1501.4 MPa and plastic strain of 31.4%.With increase of sintering temperature,yield strength drops first and rises later,and plastic strain rises first and drops later.When sintering temperature rises,alloy material gradually changes from quasi-brittle fracture to microporous aggregate fracture,and then forms large size grain and occurs intergranular fracture,which shows characteristics of brittle cleavage fracture.