Selective laser melting of boron carbide particles coated by a cobalt-based metal layer

Selective laser melting (SLM) is an additive manufacturing technology widely applied for direct fabrication of functional parts from metal powders. In this paper, the feasibility of the fabrication of three-dimensional cermet objects by SLM using 5-35 μm boron carbide particles surrounded by ∼2 μm cobalt-based layers was explored. Microstructure, composition, porosity, compressive strength and microhardness of the fabricated object were investigated. A highly porous (37%) homogeneous structure containing grains of boron carbides with 2900-3200 HV hardness embedded in the cobalt-based matrix was obtained. It was also found that new phases were formed during SLM as a result of the interaction of B4C with the cobalt-based matrix.