Published online by Cambridge University Press: 22 November 2016
Functionally graded material (FGM) has some particular characteristics due to the gradual variation of physical properties. The study on mechanical behavior of FGM is of great research value. In this work, a large scale FGM which filled with small glass spheres has been prepared by gravity assisted casting technique. The elastic material constants in static condition are measured. One optical experimental method, coherent gradient sensing (CGS), is introduced to study the mechanical behavior of FGM which has variation of material property in power-law. The governing equations of CGS which is used to represent the optics-mechanics relation of the singular field near the point of the outside force are derived based on the power-law asymptotic expansion. The experimental result shows this CGS method as a nondestructive methodology can be used to detect the damage in FGM with high accuracy.