Application of ultrasonic fatigue technology in very-high-cycle fatigue testing of aviation gas turbine engine blade materials: A review

The need for very-high-cycle fatigue (VHCF) testing up to 1010 cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and technology. This article begins with a comprehensive review of the existing available techniques that enable VHCF testing. Recent advances in ultrasonic fatigue testing (UFT) techniques are highlighted, containing their new capabilities and methods for single load, multiaxial load, variable amplitude fatigue, and combined cycle fatigue. New techniques for conducting UFT in high-temperature, humid environments, and corrosive environments are summarized. These developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade materials. New techniques that can be used for in situ monitoring of VHCF damage are summarized. Key issues in the UFT field are presented, and countermeasures are collated. Finally, the existing problems and future trends in the field are briefly described.