中国机械工程2025，Vol.36Issue(10)：2241-2248,8.DOI:10.3969/j.issn.1004-132X.2025.10.010
滚压加工AISI 4340钢螺纹根部疲劳性能的提高
Improvement of Fatigue Performances of AISI 4340 Steel Thread Root by Rolling Processes
摘要
Abstract
The rolling process was adopted to improve the fatigue performances of AISI 4340 steel bolt threads,and the optimal rolling parameters were determined by orthogonal testing with the bolt fatigue life as the evaluation index.The surface integrity and fatigue life of unrolled,under-rolled,optimally rolled,and over-rolled thread were analyzed to elucidate the thread fatigue mechanism.The results show that the rolling parameters have a significant effect on the fatigue life of AISI 4340 steel threads,with the order of significance as follows:rolling depth,spindle speed,rolling times.The optimal parameters are as:rolling depth 0.09 mm,spindle speed 40 r/min,and 3 rolling times.The surface integrity improve-ment of under-rolled samples is low,and the over-rolled samples have the largest degree of work-hardening but damaged the thread root surface.The surface roughness Sa and Sq of thread root with the op-timally rolled are reduced to 0.124 μm and 0.165 μm respectively,and the residual compressive stress is in-creased to-247.1 MPa.In addition,transition hardening is avoided with an increase in micro-hardness and the formation of a deeper deformation layer.Due to the synergistic improvement of surface roughness,micro-hardness and residual stress of the threaded root with the optimal rolling parameters,the fatigue strength was increased by 50%compared to unrolled bolts.The results indicate that the rolling process with reasonable parameters achieves the purpose of high-quality strengthening and may effectively solve the problems of high-fatigue fracture of bolts.关键词
AISI 4340钢/螺栓螺纹/滚压加工/疲劳性能Key words
AISI 4340 steel/bolt thread/rolling process/fatigue performance分类
矿业与冶金引用本文复制引用
刘宏伟,康仁科,朱祥龙,慕昊天,何方舟,陈莫..滚压加工AISI 4340钢螺纹根部疲劳性能的提高[J].中国机械工程,2025,36(10):2241-2248,8.基金项目
国家自然科学基金(52475431) （52475431）
