A study on fretting fatigue life for the Inconel alloy 600 at high temperature

Fatigue tests of the Inconel 600, a type of nickel–chromium based heat resistant alloy used for steam generator tubes in nuclear power plants, were carried out. Temperature increase to 320 °C did not change the fatigue strength much, but the fretting condition caused a significant reduction in the fatigue strength. The reduction at 107 cycles was about 70% for both of room and the high temperatures. An apparatus to realize the fretting condition has been developed and instrumented to measure the normal and friction forces. The bridge type of contact pad was fabricated of SUS 409 stainless steel. Fracture surfaces and wear scars were observed by electron microscope and the profiles of wear scar were measured by non-contact 3D-profiler.