Research on the reasonable loading method of staged follow-up rolling in low-stress cropping

• Published in: International journal of advanced manufacturing technology Vol. 120; no. 11-12; pp. 8133 - 8151
• Main Authors: Yang, Ning, Fu, Shulin, Tao, Jishao, Wang, Hang, Yang, Bohan, Xu, Jiayi, Guo, Weijian, Li, Zhishun, Zhang, Lijun
• Format: Journal Article
• Language: English
• Published: London Springer London 01.06.2022; Springer Nature B.V
• Subjects: CAE) and Design; Computer-Aided Engineering (CAD; Crack propagation; Domains; Engineering; Faults; Industrial and Production Engineering; Mechanical Engineering; Media Management; Original Article; Stress propagation; Surface properties; Staged follow-up rolling; Loading curve; Controllable crack propagation; Low-stress cropping
• ISSN: 0268-3768; 1433-3015
• DOI: 10.1007/s00170-022-09180-6

Aiming at the problems of poor surface quality and irregular crack propagation caused by unidirectional loading in low-stress cropping, a new loading method of follow-up rolling is proposed. The mechanical and crack propagation model of the rolling cropping is established. The loading relationships of material regular separation in the brittle domain and plastic domain are constructed by stages, and the mapping relationships between external force of follow-up loading and rolling time at corresponding stages in different domains are also obtained. A crack controllable low-stress cropping machine is developed to realize the follow-up rolling loading of metal bars, and an evaluation method of macro–micro comprehensive quality network with seven parameters is proposed for the cropping experimental results. This cropping method shows that the staged rolling loading achieves the most balanced and high-quality cropping effect. Further cropping research shows that, compared with the ordinary low-stress cropping, the eccentricity κ , the proportion λ , and the concave-convex extremum μ of the transient fault zone are increased by at least 5.88%, 25.44%, and 25.03%, respectively. The extremum ν and the roughness extremum ξ of the rolling outer circumferential surface are increased by 59.18% and 10.23%, respectively. The quality of the clamping outer circumferential surface is increased by 2.46–2.54 times.