Cyclic Deformation Behavior at Room Temperature and High Temperature of Domestic Inconel690 Superalloy

Uniaxial and multi-axial fatigue tests with strain-controlled and stress-controlled loading modes at 25, 200, 350℃ were conducted on domestic Inconel690 superalloy for nuclear power. The cyclic stress-strain response and cyclic plastic deformation characteristics were analyzed. The results show that at the test temperatures, the Inconel690 superalloy mainly exhibited cyclic hardening characteristics in both uniaxial and multi-axial loading processes. The ratcheting strain imcreased rapidly in the first few number of cycles and finally reached stable quickly. The Inconel690 superalloy exhibited slight cyclic softening characteristics when the uniaxial strain-controlled loading cycled in a certain number of cycles at 25 and 200℃. Under multi-axial cyclic loading conditions, an obvious non-proportional multi-axial additional hardening was observed.