摘要
文章旨在构建渗碳Cr-Ni合金钢的超高周疲劳极限预测模型。在两种应力比下对渗碳Cr-Ni合金钢开展超高周疲劳试验,结果表明,渗碳Cr-Ni合金钢的S-N特性呈现持续下降的趋势。通过扫描电镜对断口表面裂纹形貌的观测,当疲劳寿命低于5×10^(5)周次时,表面失效是疲劳试样主要失效形式,当寿命高于1×10^(6)周次时,内部夹杂-FGA-鱼眼诱发失效成为渗碳Cr-Ni合金钢的主要失效方式。利用裂纹扩展阈值对FGA尺寸进行了评估,结合El-Haddad模型,构建了基于长裂纹扩展应力强度因子阈值的疲劳极限预测模型。与他人模型预测的疲劳极限对比,得出构建的阈值应力模型预测的疲劳极限误差最小,预测结果更保守。
The purpose of this paper is to construct a predictive model for the very-high cycle fatigue limit of carburized Cr-Ni alloy steel.Very-high cycle fatigue tests were carried out on carburized Cr-Ni alloy steel under two stress ratios,and the results showed that the S-N characteristics of carburized Cr-Ni alloy steel showed a continuous downward trend.By observing the crack morphology on the fracture surface through scanning electron microscopy,it was found that surface failure was the main failure mode of the fatigue specimen when the fatigue life was less than 5×10^(5)cycles,and internal inclusion-FGA-fisheye-induced failure became the main failure mode of carburized Cr-Ni alloy steel when the life was higher than 1×10^(6)cycles.The FGA size was evaluated using the crack propagation threshold,and finally,combined with the El-Haddad model,a fatigue limit prediction model based on the threshold stress intensity factor of long cracks was constructed.Compared with the fatigue limit predicted by other models,the threshold stress model constructed had the smallest prediction error,and the predicted results were more conservative.
作者
杨溥
刘兵
邓海龙
陈雨
孔建行
于欢
YANG Pu;LIU Bing;DENG Hailong;CHEN Yu;KONG Jianhang;YU Huan(School of Mechanical Engineering,Inner Mongolia University of Technology,Hohhot 010051,CHN;Key Laboratory of Inner Mongolia for Advanced Manufacturing Technology,Inner Mongolia University of Technology,Hohhot 010051,CHN)
出处
《制造技术与机床》
北大核心
2023年第10期98-103,共6页
Manufacturing Technology & Machine Tool
基金
内蒙古自然科学基金(2021LHMS0500、2022MS05014)
内蒙古自治区直属高校基础科研业务费(JY20220233)
内蒙古高等教育研究项目(NJZY21306)
内蒙古工业大学科学研究项目(ZY202005)。
