摘要
针对不同应力比下ZG20SiMn铸钢的高周疲劳行为进行了研究,确定了应力比对ZG20SiMn铸钢的高周疲劳寿命和疲劳极限等的影响。研究结果表明,在R=0.5的高应力比下,ZG20SiMn铸钢的疲劳极限明显高于R=0.1下的疲劳极限;在相同的外加应力幅下,当R=0.1时,ZG20SiMn铸钢的疲劳寿命明显高于R=0.5时的疲劳寿命。疲劳断口形貌的扫描电子显微分析结果表明,在不同的疲劳加载条件下,裂纹均以穿晶方式萌生于ZG20SiMn铸钢试样表面,并以穿晶方式扩展。此外,钢中的鱼骨状硫化物夹杂或者呈链状分布的含钼和锰的球状化合物相会显著降低ZG20SiMn铸钢的疲劳寿命。
High cycle fatigue behavior of ZG20SiMn cast steel at different stress ratios was investigated, and the influence of stress ratio on the fatigue life and fatigue limit of ZG20SiMn steel was clarified. The research results show that the fatigue limit of the steel at the stress ratio of 0.5 is significantly higher than that at the stress ratio of 0.1. At the same stress amplitude, the fatigue life of the steel at the stress ratio of 0.1 is obviously longer than that at the stress ratio of 0.5. The observation results on fracture surfaces reveal that under different fatigue loading conditions, the cracks initiate transgranularly at the surface of fatigue specimen, and propagate in a transgranular mode. In addition, either fishbone-like sulfide inclusion or spherical compound phase containing Mo and Mn will greatly decrease the fatigue lives of ZG20SiMn steel.
出处
《铸造》
CAS
CSCD
北大核心
2013年第5期393-396,共4页
Foundry
