Influence of Heat Treatment on Microstructures and Mechanical Properties of NiCuCrMoTiAlNb Nickel-Based Alloy

As-cast NiCuCrMoTiAlNb nickel-based alloys were subjected to two-stage heat treatment, including solution treatment and subsequent aging treatment. Furthermore, the influence of heat treatment on microstructures and mechanical properties of NiCuCrMoTiAlNb nickel-based alloys was further investigated. The as-cast NiCuCrMoTiAlNb Ni-based alloys are able to experience large plastic deformation at room temperature, where nanocrystalline phases are induced. In the case of heat-treated NiCuCrMoTiAlNb nickel-based alloys, with increasing Nb content, plenty of Ni-3(Al, Ti) precipitates (gamma' phases) are distributed in the gamma matrix and they are able to become the obstacles to impede the movement of dislocations, which is responsible for increasing the yield strength of NiCuCrMoTiAlNb nickel-based alloys. Pile-up of dislocations in the vicinity of gamma' precipitates adversely influences plasticity of NiCuCrMoTiAlNb nickel-based alloys.