弹簧钢55SiCrA轴向疲劳行为的试验研究  

Axial Tension and Compression Load Fatigue Behavior and Mechanism of Spring Steel 55SiCrA

作　　者：肖金福[1] 刘雅政[1] 孙小军[1] 孙景宏[1] 谢建新[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《钢铁》2011年第1期80-85,共6页Iron and Steel

基　　金：北京市科技计划资助项目(D0404001040221)

摘　　要：随着对汽车轻量化和安全性要求的不断提高,改善疲劳性能成为弹簧钢研究与开发的一个重要主题。在Amsler HFP 5000高频疲劳试验机上研究了弹簧钢55SiCrA轴向拉-压加载的疲劳性能,测定了其条件疲劳极限及S-N曲线,利用扫描电镜（SEM）和E-DAX对疲劳断口及夹杂物进行观察,对断口进行了宏观和微观分析,研究了疲劳破坏的机制。试验结果表明：试验钢的条件疲劳极限为820 MPa,σ-1p/σb=0.562（Nf=107）;疲劳裂纹源主要起源于表面,较大的夹杂物（20~30μm）也成为疲劳裂纹源;疲劳裂纹稳定扩展区的疲劳条带宽度为1.5~2.0μm。Improving the fatigue properties of spring steel has became an important theme of RD on spring steel with continuous improvement requirements of automotive lightweight and safety.The axial tension and compression load fatigue behavior of spring steel 55SiCrA was studied by Amsler HFP 5000 high-frequency fatigue testing machine.Fatigue limit and S-N curve were measured.Fracture surfaces and non-metallic inclusions were observed by SEM and E-DAX,and mechanism of fatigue failure was analyzed.The results show that the fatigue limit of 55SiCrA is 82 0 MPa and σ-1p/σb is 0.562（Nf=107）.Fatigue crack initiates mainly from surface and non-metallic inclusions（20-3 0 μm）.Fatigue striation in fatigue crack growth zone is 1.5-2.0 μm in width.

关 键 词：弹簧钢 疲劳行为 非金属夹杂物 疲劳机制 

分 类 号：TG142.15[一般工业技术—材料科学与工程]