抄録
Dependence of the mechanical properties of P/M extruded material of titanium with the silicon nitride (Si_3N_4) on solid phase decomposition of Si_3N_4 was investigated. Si_3N_4 particles within Ti composite powder were decomposed during the spark plasma sintering at 1223 K with 30 MPa pressure for 3.6 ks, and then, nitrogen and silicon atoms originated in Si_3N_4 were defused into titanium matrix. The extruded of Ti-1.0 mass% Si_3N_4 powder material had ultimate tensile strength (UTS): 1139 MPa, and yield stress (0.2% YS): 1065MPa. UTS and 0.2%YS of P/M extruded material of Ti with 1.0 mass% Si_3N_4 were 2 and 2.5 times compared to extruded pure Ti powder material, respectively. It was considered that the solid solution strengthening of both nitrogen and silicon originated in Si_3N_4 caused high strength of P/M extruded material of Ti with 1.0 mass% Si_3N_4.
