Influence of isolated structural defects on the static mechanical properties of PBF-LB/M components

Abstract

Since the microstructure of components made by Laser-based powder bed fusion of metals (PBF-LB/M) is directly affected by the melting and solidification, mechanical properties are very sensitive to deviating process conditions. If deviations occur, local defects may remain within the microstructure. The impact of isolated defects on the resulting mechanical properties is only poorly understood. Since PBF-LB/M processes are increasingly used in industrial applications, fundamental systematic studies on the effects of structural defects on the mechanical properties are necessary to ensure quality. Thus, single defined structural defects of different dimensions are reproducibly placed in PBF-LB/M samples and used for static-mechanical tests. The results of tensile testing are compared with structural mechanical simulations, which provide insights into the prevailing stress and strain distributions. The achieved results show that isolated internal defects have only a minor influence on static strength parameters. Particularly with larger defect sizes, the values determined for tensile strength and yield strength showed only minor impairment.