Control of texture and microstructure in additive manufacturing of stainless steel 316 L

Abstract

This investigation deals with exploring the effect of rotation scan strategy on microstructural evolution and hence mechanical behaviour of 316 L stainless steel prepared by additive manufacturing using selective laser melting technique. Higher anisotropy has been observed for samples where no hatch rotation was employed compared to the samples where a hatch rotation was involved during printing. The morphology of grains gets perturbed for samples prepared by hatch rotation 60˚ and hatch rot 74˚ when compared to the samples prepared using no hatch rotation or a hatch rotation of 90˚. The crystallographic texture component of the sample consists of a combination of < 100 > and < 110 > orientation (// building direction) except for the hatch rot 60˚ sample where the texture comprises of only < 110 > . It has been noticed that texture control is possible through giving a rotation such as 60˚ or 90˚. The samples prepared without any hatch rotation exhibited higher strain hardening due to combined action of slip and twin activity when compared to hatch rot 60˚ sample where < 110 > texture reduces the deformation mechanism to slip only. This study paves a new pathway to control the mechanical properties by tuning the appropriate texture along the BD.