Influence of shape distortion on the precision of holes in parts fabricated by metal binder jetting

Abstract Metal binder jetting (MBJ) is an additive manufacturing (AM) technology split into two process steps: printing and sintering. Firstly, product built up layer-by-layer by the selective deposition of a agent on powder bed. Secondly, thermal treatment (sintering) consolidates metal structure. MBJ currently becoming more attractive reason high potential scalability, cost-effective production wide range available material feedstocks. However, transition towards industrial scale restrained critical control dimensional geometrical precision parts after sintering operation. In fact, geometry affected anisotropic change or even shape distortion. This study aims at investigating through holes. Three sample geometries were designed, having hole with axis perpendicular to building direction located different levels along height. Samples measured coordinate measuring machine before sintering, in order assess shrinkage any change. Results highlight inhomogeneous volumetric linear three geometries, which influenced position plane. A macroscopic deformation parallelepiped was also evidenced, caused superposition layer shifting originated printing, frictional forces between surface alumina support during Such distortion significantly affects form error