Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : December 22, 2018 - December 24, 2018
The Mechanoluminescence materials to use in this study consists of SrAl2O4 : Eu (Strontium aluminate added with europium). It has peak wavelength of about 520 [nm], and has high luminance to deformation and stress. The europium at the center of luminescence emit light by the piezoelectric effect which is caused when crystal is deformed. Therefore we produce an inspection method which can visualize stress inside the material using the theory of elasticity. We derive a general solution for many circular cylindrical holes that are free boundary to an elastic medium (matrix) of infinite extent under in-plane problem. These many holes have different radii and different central points. When there are many holes in the matrix, we consider the matrix as a poroelastic matrix. The matrix is subjected to arbitrary loading, for example, by uniform stresses. Using these solutions, we observe the graph of brightness and maximum principal stress around the holes from mechanoluminescence materials, general solution of elasticity and numerical solution of FEM. In this study we present several numerical examples graphically.
