Abstract: Microstructure, hardness, mechanical properties and tensile fracture morphology of as-forged TZM superalloy annealed at different temperatures were investigated, and the reasons for the generation of different fracture morphologies were analyzed. The results show that the microstructure, mechanical properties and fracture morphologies of the TZM alloy with a deformation of 82% change significantly when annealed at different temperatures. With the increase of annealing temperature, the microstructure of the TZM alloy changes from as-forged to as-recrystallized and gradually coarsenes, where the strength and hardness also decrease, and the fracture morphology varies with the annealing temperature. When the annealing temperature is lower, the fracture morphology is of cleavage river pattern. While when the annealing temperature is higher, the morphology is of cleavage river pattern accompanied by partial intergranular fracture. When the TZM alloy is annealed at 1300 ℃ for 90 min, the microstructure and mechanical properties are preferable, and the fracture mode is ductile.

Key words: TZM superalloy, annealing temperature, microstructure, mechanical properties, fracture morphology