Understanding creep behaviors of additively manufactured 316L stainless steel via void characterization

Abstract

Additively manufactured (AM) 316L stainless steel (SS) has been reported to have low creep resistance compared to its conventionally made counterparts. Herein, we quantitatively characterized the voids in a creep-ruptured AM 316L SS specimen and those in a conventional specimen ruptured under the same testing condition. The AM 316L SS contained more small creep voids and fewer large ones. 3D reconstructions showed the spatial distribution of the small voids in AM 316L SS followed the melt pool tracks, which was attributed to the grain structure unique to the laser process. The observations explained the creep behaviors of the two specimens.

Keywords

• Laser powder bed fusion
• x-ray tomography
• electron backscattering diffraction
• stainless steel
• creep