Evolution of Metal Surface Topography during Fatigue

Metals

Ke Lu¹  Darong Zhu²  Tao Liu²  Lu Xu²  Fangbin Wang² 

[1] Key Laboratory of Construction Machinery Fault Diagnosis and Early Warning Technology, Anhui Jianzhu University, Hefei 230601, China;School of Mechanical and Electrical Engineering, Anhui Jianzhu University, Hefei 230601, China;

关键词: surface topography;    fatigue damage;    co-occurrence matrix;    shearlet transform;   

DOI  :  10.3390/met7020066

来源: DOAJ

【 摘 要 】

Changes in surface topography reflect the state of fatigue damage. In this paper, a new method to characterize metal surface topography during fatigue has been proposed. Firstly, we acquired surface topography images based on machine vision and separated them into roughness, waviness, and form error images through a shearlet transform. Secondly, we constructed gray co-occurrence matrixes of the obtained surface topography images and calculated the characteristic parameters, such as contrast, correlation coefficient, energy, and entropy for all the original and separated images. Then, taking a Q235 steel specimen as an example for testing, the experimental results and theoretical analysis demonstrate that the parameter contrast increases while energy, correlation coefficient and entropy decrease gradually with number of loading circles, which reach their maximum and minimums before fracture, respectively.

【 授权许可】

Unknown