铼对铱显微组织和力学性能的影响

借助光学显微镜、扫描电镜和万能力学试验机研究元素铼对铱显微组织和力学性能的影响。结果表明,添加元素铼可以细化铱的晶粒,显著改善铱的显微组织。随着铼含量的增加,在固溶强化和细晶强化作用下,铱铼合金的屈服强度和抗拉强度呈现先上升后下降的趋势,当铼质量分数为7.0%时屈服强度和抗拉强度达到最大值为472.0和526.0 MPa;而在铱中添加铼以后,铱铼合金的延伸率先降后升,其中纯铱的延伸率最高为2.52%。室温下铱铼合金的断口呈脆性沿晶断裂和脆性穿晶断裂的混合断裂模式,加入元素铼后断口形貌中脆性穿晶断裂区域明显增多。

Effect of Rhenium on Microstructure and Mechanical Properties of Iridium

Microstructures and mechanical properties of Ir with Re addition were investigated through OM, SEM and universal testing machines. The results show that the addition of Re can refine grains, and obviously improves the microstructure. With increasing of Re content, the yield strength and tensile strength of Ir-Re alloy were increased first and then decreased. With addition of 7.0% Re and under the effect of solid solution strengthening and fine grain strengthening, the yield strength and tensile strength of the alloy reach the maximum of 472.0 and 526.0 MPa. With addition of Re, the elongation of Ir-Re alloy was decreased first and then increased. The elongation of pure iridium was the highest to be 2.52%. The fracture mode of Ir-Re alloy was mixture ofbrittle intergranular fracture and brittle transgranular cleavage fracture. With addition of Re, the brittle transgranular cleavage fracturearea was increased significantly.