不同强度级别低合金高强钢疲劳断裂行为分析  

Analysis of fatigue fracture behavior of low-alloy high-strength steel with different strength grades

作　　者：翟雁[1] 郭晓波[1] 丁再超 李志强 ZHAI Yan;GUO Xiao-bo;DING Zai-chao;LI Zhi-qiang(School of Mechanics Engineering,Anyang Institute of Technology,Anyang 455000,China;Comprehensive Section of Anyang,Zhengzhou Railway Bureau,Anyang 455000,China;Xiangyu Medical Co.,Ltd.,Anyang 455000,China)

机构地区：[1]安阳工学院机械工程学院,河南安阳455000 [2]郑州铁路局集团有限公司安阳综合段,河南安阳455000 [3]河南翔宇医疗设备股份有限公司,河南安阳455000

出　　处：《塑性工程学报》2023年第7期145-150,共6页Journal of Plasticity Engineering

基　　金：国家自然科学基金-河南联合基金资助项目(U1204613)。

摘　　要：选取5种不同强度级别的低合金高强钢材料开展疲劳特性研究,对材料的微观组织和力学性能进行了对比分析。在此基础上,通过施加应力控制的拉-压疲劳载荷,获取了应力比为0.1时,5种材料的疲劳特性应力幅-疲劳寿命(S-N)曲线;并基于试验和经验公式,获取了应力比为-1时的S-N曲线,开展了不同强度材料疲劳特性对比了分析;对5种低合金高强钢的疲劳失效进行了分析,选取不同载荷下具有代表性的疲劳断口形貌进行对比分析。结果表明,随着抗拉强度的提升,所研究的低合金高强钢的疲劳极限不断提高;当应力比为-1时,疲劳极限与抗拉强度的比值约为0.5;上述材料的疲劳极限与抗拉强度近似成线性关系;施加循环载荷后,样品表面发生侵入或挤出,进而形成初始的微裂纹,并最终产生宏观裂纹导致开裂。The fatigue characteristics of five kinds of low-alloy high-strength steel materials with different strength grades were studied.The microstructure and mechanical properties of the materials were compared and analyzed.On this basis,the stress amplitudefatigue life(S-N)curves of fatigue characteristics for the five kinds of materials were obtained by applying stress-controlled tensioncompression fatigue loads when the stress ratio was 0.1.Based on the test and empirical formulas,the S-N curves with strain ratio of-1 were obtained and the contrastive analysis of fatigue characteristics of materials with different strengths was carried out.The fatigue failure of five kinds of low-alloy high-strength steel was analyzed.The representative fatigue fracture morphologies with different loads were selected for comparative analysis.The results show that the fatigue limit of the studied low-alloy high-strength steel increases with the increase of tensile strength.When the stress ratio is^(-1),the ratio of fatigue limit to tensile strength is about 0.5.The fatigue limit of such materials is approximately linear with tensile strength.After cyclic loading is applied,the surface of the samples is invaded or extruded,which leads to the formation of initial microcracks and eventually macroscopic cracks leading to cracking.

关 键 词：低合金高强钢 疲劳寿命 应力幅-疲劳寿命曲线 断口形貌 

分 类 号：TG146.21[一般工业技术—材料科学与工程]