Research on the sensor for detection of carburized case depth based on nonlinear ultrasound

Abstract

Carburized case depth may be characterized by using nonlinear ultrasound. However, the excitation and receiving sensors are difficult to control in the same conditions in each experiment and the operation process is complicated, therefore, a specialized sensor needs to be developed. In this work, the influence of the backing materials with different constituents and thickness on the characteristics of sensors is investigated. The structure of the specialized sensor is designed, applied, and verified in the detection of carburized case depth based on nonlinear ultrasound. The results show that the backing layer consists of three-dimensional graphene (3DG) 1wt%/tungsten powder 80wt%/epoxy resin has high acoustic impedance and attenuation characteristics, the backing layer with thicknesses of 8 mm has high sensitivity and residual vibration suppression, the specialized senor simplifies the detection procedure, and improves the efficiency and stability of detection.