HIP-Re 组织及力学性能

采用粉末冶金热等静压技术制备了HIP-Re纯铼材料,分析了不同热处理状态对材料微观结构及室温和高温性能的影响。结果表明,热处理温度对材料拉伸性能影响较大,经1 800℃/1.5 h真空处理HIP-Re抗拉强度达到1 196 MPa,伸长率为19.1%;2 000℃抗拉强度达到69 MPa,伸长率达17%以上。粉末冶金铼的晶粒组织多为2～8μm细小等轴晶,HIP-Re断裂方式为沿晶断裂与穿晶断裂共同作用,高温断裂方式为晶间断裂与滑移断裂,在拉伸形变过程中,Re材料内部产生了大量协变的裂纹及微孔,裂纹扩展连接导致断裂。

Microstructure and Mechanical Properties of HIP-Re Metal

Pure HIP-Re metal were prepared by powder metallurgy HIP method,and the microstructure and tensile properties at room temperature and 2 000℃ of specimens after different heat treatment procedure.It can be found that different heat treatment procedures affect the resulting tensile properties significantly.The results indicate HIP-Re specimens heating treatment of 1 800℃/1.5h exhibit the greatest ultimate strength and elongation with 1 196 MPa and 19.1% at room temperature,the high temperature 2 000℃ tensile properties of 69 MPa and 17%,respectively.The PM Re metal microstructure exhibit fine and equiaxed grains with the size of 2 to 8 μm,a mixtured of intergranular and transgranular fracture is observed for HIP-Re metal fractured at room temperature,and the dominant fracture mechanism at high temperature in the HIP-Re metal are intergranular fracture and slip during deformation with a lot of porosity and micocracks occurring.