Effect of Defect Size on Fatigue Strength of Inconel 718 Fabricated by Selective Laser Melting

摘要

SLM technique was used to build many kinds of materials and results proved with successeven when the material is a difficult-to-machine, such as Inconel 718. On the other hand, it isimpossible to prevent the occurrence of internal defects in SLM parts completely. Internal defects leadto deterioration of mechanical properties, represented by fatigue property. However, the relationshipbetween internal defect size and fatigue strength deterioration is still unclear. To elucidate the effect ofdefects on fatigue behaviour of Inconel 718 fabricated by SLM, fatigue tests were conducted withspecimen containing various defect sizes. Specimens containing defects whose diameter is about 400μm don’t show any significant decrease in fatigue strength.