热处理对粉末冶金Inconel 718高温合金组织及性能的影响

Powder metallurgy (P/M) Inconel 718 superalloy was prepared through hot isostatic pressing (HIP) route from super-speed plasma rotating electrode process (SS-PREP) powder. Effect of heat treatment on the microstructure and mechanical properties of superalloy was studied. The results indicate that Inconel 718 superalloy powder prepared by SS-PREP method has good sphericity and excellent HIP process performance, and its particle size distribution is uniform; with the increase of solution temperature, the grain boundary of the alloy gradually becomes shallower, which indicates that the amount of precipitated phase at grain boundary gradually decreases. After aging treatment, a large amount of needle-like δ phases precipitate along grain boundary, at the same time, a small amount of MC carbides precipitate along the grain boundary as well. The RT tensile strength of the alloy after solution heat treatment at 1020℃ can reach 1404 MPa, and the HT tensile strength of the alloy at 650℃ is 1153 MPa after solution treatment at 980℃, and the comprehensive properties of the alloy with solution treatment at 980℃ are better.