Anisotropy of mechanical properties of products manufactured using selective laser melting of powdered materials

Abstract

Causes of the appearance of anisotropy of properties in products manufactured according to the technology of selective laser melting of metallic powder materials are investigated. The results of an evaluation of mechanical properties of the samples made of Ti–6Al–4V and VT6 titanium-based alloys and Inconel 718 refractory nickel alloy in various directions are presented. The dependence of their mechanical properties on the orientation of billets relative to the working platform of the installation is presented. An analysis of microslices of the Ti–6Al–4V alloy showed that the direction of the granular structure for a rectangular sample corresponds to the growth direction, while, when manufacturing thin elements of a net construction, other thermal processes flow due to their smaller cross section, which affects the crystallization conditions and microstructure being formed. Grain directions and shapes change depending on the slope angle of the element of the net structure.