Investigation of Vacuum Hot-Press Sintering Temperatures on the Sintered Characteristics of Cr-31.2 mass% Ti Alloys

摘要

The aim of this work is to find the optimal sintering parameters of Cr-31.2 mass% Ti alloys and simultaneously investigate the effects of the TiCr2 Laves phases. In this study, Cr-31.2 mass% Ti alloys are fabricated by vacuum hot-press sintering. Different compositions of submicron titanium (760 nm) powders are added to micron chromium (4.66 mu m) powders. The experiments utilize various hot-press sintering temperatures (1250, 1300, 1350 and 1400 degrees C) with the pressure maintained at 20 MPa for 1 h, respectively. The experimental results show the optimal parameters of the hot-press sintered Cr-31.2 mass% Ti alloys to be 1400 degrees C at 20 MPa for 1 h. The relative density reaches 99.96% and the hardness and TRS (transverse rupture strength) reach 81.93 HRA and 475.73 MPa, respectively. In addition, the increase in temperature of the hot-press sintering is effectively decreased the Cr3Ti3O and slightly enhanced TiCr2 phases, which will lead to the better mechanical properties. Significantly, the optimal hot-press sintered Cr-31.2 mass% Ti alloys possess a dense microstructure, excellent mechanical property and good electrical conductivity value (1.51 x 10(4) S cm(-1)).