摘要
超高周疲劳是指疲劳周次达到 10 8及其以上时材料的疲劳行为。与一般认识的疲劳行为不同之处是 ,超高周疲劳发生在传统疲劳极限以下 ,因此研究超高周疲劳行为有助于进一步理解疲劳的本质和疲劳机理。文中综述近几年超高周疲劳研究的进展 ,包括超高周疲劳的典型特征 ,如S—N曲线的特点、断口特征、断面上的鱼眼形貌以及裂纹的起源与扩展特征等 ;分析疲劳机理和相关的模型以及简要探讨影响超高周疲劳的一些因素 ,如加载频率、加载方式、氢的作用等。
High cycle fatigue is the most common reasons for failure of components and structures Most of the fatigue tests were accomplished below ten to hundreds millions of cycles in literature However, railway wheels and rails, offshore structures, bridges, etc , have to endure fatigue loads up to ten billion cycles without failure Very high cycle fatigue (VHCF) is the study of fatigue failure behaviors of materials and structures at and beyond hundreds millions of cycles Even in some ferrous materials, which were assumed to have a fatigue limit, very high cycle fatigue failures are detected Till now, there are few of fatigue tests, failure analysis and mechanisms of VHCF fatigue, compared with the abundant result on LCF and HCF regime This paper summarizes works of VHCF fatigue in recent years, such as the observations on fish eye, which is one of the typical characteristics of VHCF fatigue, fracture origin and discussions about the shape of S—N curve, etc The present work also analyzes the fatigue mechanisms and concludes some theoretical models of VHCF fatigue Some possible and prospective aspects of future researches are also proposed
出处
《机械强度》
CAS
CSCD
北大核心
2004年第5期526-533,共8页
Journal of Mechanical Strength
关键词
超高周疲劳
疲劳机理
疲劳极限
内部裂纹起源
Very high cycle fatigue
Fatigue mechanism
Fatigue limit
Crack initiation
