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 degrees C, 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 degrees C 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 degrees C has lower mechanical properties and the surface of the tensile fracture shows brittle rupture at the room temperature.