摘要
采用四点弯曲疲劳试验研究了不同应力水平下无镍高氮不锈钢的疲劳行为,并对材料疲劳裂纹的微观形貌、萌生位置及扩展路径进行了分析。结果表明,试验钢疲劳为多裂纹起裂,随着应力水平的升高,裂纹总长度逐渐增加,当应力水平接近材料屈服极限时,裂纹长度趋于稳定;裂纹大多数在滑移带处萌生,裂纹在扩展过程中产生了扭曲、偏移和分叉现象;裂纹在晶内主要沿单滑移带或多滑移带交替扩展,穿过晶界或孪晶界时大多发生了偏转。
Using four-point bending fatigue test studied the fatigue behavior of nickel free high nitrogen stainless steel in different stress levels, and the micro morphology, initiation position and propagation trace of fatigue crack were ana- lyzed. The fracture of experimental steel was multiple cracks, and the total crack length increased gradually with the in- crease of stress level. The crack length tends to be stable when the stress level was close to the yield limit of the material. Most of the cracks initiated at the slip zone, and the crack were distorted, migrated and bifurcated in the process of crack propagation. The crack propagated mainly along single slip band or multiple slip bands in the grain and deflected when crack crossed the grain boundary or twin boundary.
出处
《钢铁》
CAS
CSCD
北大核心
2017年第10期89-93,共5页
Iron and Steel
基金
河北省自然科学基金资助项目(E2016203436
E2016203256)
关键词
四点弯曲疲劳
无镍奥氏体钢
裂纹萌生
裂纹扩展
有限元
Key words： four-point bending fatigue
nickel free austenite steel
crack initiation
crack propagation
finite elementmethod
