热轧温度对低密度Nb-Ti-Al-V-Zr-C合金性能的影响

对经挤压开坯的一种低密度铌合金分别在1000,1100,1200℃下进行了热轧,并利用光学显微镜、扫描电镜和场发射透射显微镜对试样的组织形貌进行了表征;对合金的室温和高温拉伸强度、延伸率进行了测试。结果表明:在1200和1100℃温度下热轧时,合金均具有优良的室温和高温性能,室温强度在600MPa以上,室温塑性大于12%,高温下的强度在80MPa以上,高温塑性大于30%,且随轧制温度升高,抗拉强度降低,塑性增大;而在1000℃下热轧时,室温和高温力学性能均较低,且室温拉伸断口表现为脆性断裂。

Effects of Hot-rolling Process on the Microstructure and Mechanical Properties of Nb-Ti-Al-V-Zr-C Alloy

The hot rolling process of a low-density Nb-based alloy was carried out at 1000,1100 and 1200 ℃,respectively.The microstructures of the samples were characterized by the optical microscopy,SEM and field emission TEM,and the tensile strength and elongation of the alloy were also tested.The results show that the alloys hot-rolled at 1200 and 1100 ℃ have excellent room and high temperature properties,the room temperature strength reaches 600 MPa and the elongation more than 12%,the high temperature strength reaches 80 MPa and the high-temperature elongation above 30%.It is also found that the tensile strength decreases and the plasticity increases with the increase of the rolling temperature.But the alloy hot-rolled at 1000 ℃ has lower mechanical properties and the surface of the tensile fracture shows brittle rupture at the room temperature.