Ultrasonic Detecting Method of Mechanical Interface Contact Distribution

Contact analysis of mechanical interface has been an important engineering problem. Based on the interaction principle between ultrasonic wave and imperfect interface, experimental method on contact area and distribution of steel-steel interface with pulse-echo technique is presented in this paper. In the method, ultrasonic echo signal being denoised and transformed with Fourier transform to get amplitude value, two-dimensional characteristic data array is obtained by scanning detection system to describe the interface. After low resolution arrays are registered with Fourier-Mellin transformation and Taylor series algorithm, the scanning detection resolution is improved by POCS(Projection onto convex sets) algorithm with multiple low resolution arrays. The experimental results show that the experimental method to evaluate the interface contact area and distribution is reliable, and has practical value on analysis and research of real contact engineering problems.