Servin-Castañeda Rumualdo, Arreola-Villa Sixtos Antonio, Perez-Alvarado Alejandro, Calderón-Ramos Ismael, Torres-Gonzalez Ruben, Martinez-Hurtado Alonso
Facultad de Ingenieria Mecanica y Electrica, Universidad Autónoma de Coahuila, Unidad Norte, Monclova Coahuila 25750, Mexico.
Facultad de Ingenieria Mecanica y Electrica, Universidad Autónoma de Coahuila, Unidad Torreon, Torreon Coahuila 27410, Mexico.
Materials (Basel). 2022 May 13;15(10):3524. doi: 10.3390/ma15103524.
Backup rolls are the main tool in a four-high rolling mill; the rolling forces applied in load cells promote the fatigue of the material due to mechanical contact between backup rolls and work rolls. This work investigated the causes of recurrent failures in backup rolls, with cracking always initiated on the surface of the roll body and finishing in the main radius between neck and roll body. Aiming to find the causes of failure, visual inspection and morphology of the fracture were performed, complemented with mechanical tests of hardness on the stress concentration area, in addition to validating the results by applying the finite element method, using ANSYS Mechanical Static Structural Software. It was concluded that the fatigue crack initiated on the surface of BUR due to work hardening continued growing up over the fatigued material, creating beach marks, and finally, a fracture occurred in the main radius of BUR due to stress concentration. The work hardening is the main cause of spalling on BURs and other mechanical components exposed to mechanical contact.
支承辊是四辊轧机中的主要工具；称重传感器施加的轧制力会因支承辊与工作辊之间的机械接触而加剧材料的疲劳。这项工作研究了支承辊反复出现故障的原因，裂纹总是在辊身表面开始，并在辊颈和辊身之间的主半径处结束。为了找出故障原因，对断裂进行了目视检查和形态分析，并对应力集中区域进行了硬度机械测试，此外还使用ANSYS Mechanical Static Structural软件应用有限元方法验证了结果。得出的结论是，由于加工硬化，疲劳裂纹在支承辊表面开始，在疲劳材料上持续扩展，形成海滩状痕迹，最终，由于应力集中，支承辊的主半径处发生断裂。加工硬化是支承辊和其他承受机械接触的机械部件剥落的主要原因。
