On the fatigue crack growth behavior in 316L stainless steel manufactured by selective laser melting

摘要

Direct manufacturing techniques such as selective laser melting (SLM) enable material efficient production of individual and complex components in a short period of time. But often these components suffer from process induced imperfections, primarily micro-pores and high residual stresses. Under fatigue loading these two kinds of inherent weaknesses lead to premature failure and consequently fairly low performance in many alloys processed by SLM. The fatigue performance of stainless steel 316L has been investigated. Thorough microstructural analyses were carried out using electronoptical techniques and X-ray diffraction in order to shed light on the process-microstructure-property relationships for this alloy. Fatigue property analyses have not been carried out in such depth so far. The results obtained clearly show that 316L is a promising candidate for cyclically loaded parts manufactured by SLM. Primarily attributed to the high ductility directly following SLM processing, the 316L stainless steel shows fatigue properties similar to conventionally processed material in its as-built condition.