Experimental research of inside mechanical behavior based on advanced light source

Failure of key materials is a significant problem in various important engineering fields including aerospace, bridge, architecture, military-industrial, and high-speed train, etc. Materials failure and fracture are the fundamental causes of many engineering disasters and safety accidents. As we all know, visible macroscopic material failure is determined by the internal microscopic mechanical behavior which can not be directly observed. Therefore, precise experimental observation and research of internal microscopic mechanical behavior are the important foundation for revealing the mechanisms of materials failure and fracture. Conventional experimental techniques based on ultrasonic, visible light, electromagnetism, etc., are unavailable for direct observation with high resolution of internal mechanical behavior. Fortunately, the development of advanced light sources including synchrotron radiation and neutron source in recent years makes it possible to conduct in situ experimental research of materials inside failure processes. Both domestic and overseas research works of internal mechanical behavior experiments on the basis of advanced light sources are reviewed in this manuscript in two aspects of space and time. In spatial scale, the research works are organized into three scales of millimeter and micrometer, micrometer and sub-micrometer, nanometer according to spatial resolution. As for time scale, the research works are divided into static and quasi-static tests, and dynamic tests according to time resolution. At last, the challenges of experimental methods for internal observation in solving the problem of material failure and fracture are analyzed. And the development tendency of internal mechanical behavior experimental theories, methods and techniques based on advanced light sources are also discussed.