Abstract
Surface flaws on valve springs in automobile engines are one of the crucial factors which affect the fatigue life of valve springs together with harmful non-metallic inclusions and surface decarburization. Through the fatigue tests of high tensile strength springs and nitrided springs with artificial longitudinal flaws, the influence of surface flaws on fatigue lives were investigated.Fatigue lives of both springs lowered as the depth of flaws increased, however, in this experiment, when flaw depth was not deeper than 0.05mm, no lowering of each fatigue strength was recognized. It was considered as this reason, that the large compressive residual stress of the surface layer effectively suppressed propagation of fatigue crack.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
