Analysis of crack defects of 20CrMnMo gear blank by ultrasonic flaw detection
SHI Feiyang1, CHEN Changhua2, DOU Yiheng1, CHEN Jiping1, QIAN Jianqing1
1. School of Metallurgy Engineering, Anhui University of Technology, Ma'anshan 243002, China; 2. Technology Center, Nanjing Develop Advanced Manufacturing Co., Ltd., Nanjing 210048, China
Abstract：During the ultrasonic flaw detection of gear blanks of 20CrMnMo forged by one forging plant, it was found that there were some cracks inside. The gear blanks with defects were dissected and sampled. The causes of internal cracks inside of gear blanks were analyzed by macroscopic examination, metallographic examination, fracture analysis, scanning electron microscope examination. The results showed that the incomplete welded bubbles and clustered inclusions in the gear blank led to formation of cracks under the action of structural stress and thermal stress.
2023, Vol. 41 
