Numerical modeling and experimental study of microcrack detection in grinding burn using high order strain mode

A novel method for the microcrack detection in grinding burn based on the high order strain mode was proposed in this study, which is especially suitable for the microcrack detection in small workpiece. The governing equations for solving the strain mode and the displacement mode were firstly given. With the help of the ANSYS software, the numerical modal analysis for a platelike grinding specimen without and with a microcrack was carried out. The first five order bending natural frequencies, displacement modes, and strain modes were obtained, respectively. In order to verify the effectiveness of the proposed method, the experimental modal analysis for a platelike grinding specimen without and with an artificial microcrack was performed based on the high-frequency vibrator. The results show that using the high order strain mode or increasing the number of the strain modes both can improve the accuracy of the microcrack detection. Moreover, the strain mode is more sensitive to the microcrack than the displacement mode. The findings confirm that the high order strain mode has the significant sensibility to the local structure damage and provide a possibility to establish a nondestructive detecting system for the microcrack detection.