Abstract：Improving the fatigue properties of spring steel has became an important theme of R&D on spring steel with continuous improvement requirements of automotive lightweight and safety. In this paper, 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 showed that the fatigue limit of 55SiCrA was 820MPa and σ-1p/σb was 0.562(Nf=107). Fatigue crack initiated mainly from surface and non-metallic inclusions (about 20、30μm). Fatigue striation in fatigue crack growth zone was 1.5~2.0μm in width.
2011, Vol. 46 
