Abstract
A fundamental study of a nondestructive detection method for metal fatigue in sheet materials with simple equipments was performed by using laser-induced thermal vibration. In the experiments, changes in amplitude of laser induced thermal vibration were found around the target portion. This position corresponded to the site where analysis indicated that the stress concentrated. Precise measure ents of the vibrations can be applied to analyze two-dimensional stress distributions. In this paper, we measure the amplitude of vibration on a metal sample by the laser-induced thermal vibration and analyze the stress distribution by finite element method when stress was added to the load. We examine the relation between the site of large amplitude place and concentration of stress.
