Shock Activation and Hot-Press Sintering of Si_3N_4 Powder
LIU Jing yu 1, CAI Qing yu 2, ZHANG Shu hua 3 (1. Department of Physics and Chemistry of Changsha University, Changsha 410003, China) (2. College of Science,3. College of Aerospace and Materials Engineering, National Univ. of Defense Technology,
Si 3N 4 powders have been pre treated by shock activating and hot pressed into Si 3N 4 ceramics. Three kinds of shock pressure, and three different sintering temperatures are used in the experiments, SEM, TEM and X ray Diffraction have been used to analysis the structure of the Si 3N 4 powders and ceramics. The properties of Si 3N 4 ceramic have been tested. The results show that shock activation give positive action to the densification of Si 3N 4 powder and the increase of properties of the Si 3N 4 ceramics; the ceramic parts shocked under 40 GPa and sintered under 1800℃ have the best properties. The bend strength reaches 1107.2 MPa, at the same time, the fracture toughness reaches 12.20 MPa.m 1/2 .
【CateGory Index】： TB44