[15P-T4-04] Evolution of Microstructure and Mechanical Properties of Powder Metallurgy TC18 Prepared by Hot Isostatic Pressing
キーワード： Hot isostatic pressing (HIP), Titanium alloy, powder metallurgy
In this paper, the TC18 pre-alloyed powder prepared by plasma rotating electrode process was used for hot isostatic pressing (HIP). The influence of HIP temperature and heat treatment on the microstructure and mechanical properties of HIPed TC18 was investigated. The results show that. The TC18 alloy is transformed β structure when HIPed at 900℃ and bimodal structure with equiaxed α phase andtransformed β at 800℃. The strength of TC18 with bimodal structure increased significantly with the decrease of aging temperature when double annealing. The strength,elongation and fracture toughness are 1499 MPa, 8.5% and 35 MPa·m1/2 when aging at 580℃. After triple annealing, the strength of bimodal structure TC18 is lower compared with double annealing, but the elongation and fracture toughness can reach 20.1 % and 49.9 MPa·m1/2.