The present situation and future problems in ultrasonic fatigue testing – Mainly reviewed on environmental effects and materials’ screening

Ultrasonic fatigue testing results of various materials is briefly reviewed. The emphasis is focused upon rapidity and effectiveness of fatigue testing which enable screening tests for structural materials such as steam turbine blade materials. It is also exemplified that ΔKth can be measured at the very slow crack propagation rate between 10−8 and 10−14 m/cycle. Fatigue and corrosion fatigue behavior of structural materials in very high cycle regime can be investigated by use of the ultrasonic fatigue testing. Some problems such as heat generation in specimen and frequency effect in ultrasonic fatigue testing are also briefly discussed.Finally, a couple of future problems to be solved in ultrasonic fatigue testing are touched on briefly.