Investigation of mechanical, microstructural and thermal behavior of CoCrMo alloy manufactured by selective laser melting and casting techniques

Abstract

A route of increasing development in additive manufacturing (3D printing) process using metal alloys is the selective laser melting (SLM). 3D building components is possible by laser power that completely melts the metal powder particles. SLM was applied in a biomaterial of CoCrMo alloy, to study the mechanical properties and microstructural characterization in comparison of the conventional technique – lost wax casting. The gas atomized powder was investigated by their physical (as apparent density, bulk density and flow rate) and chemical properties (X-ray fluorescence). Standard samples evaluated the mechanical properties as yield strength, elongation, elastic modulus, transverse rupture strength and the Vickers hardness. Microstructural characterization was performed using optical microscope (OM) and scanning electron microscope (SEM-EDS). Thermal analysis of CoCrMo alloy were investigated using thermomechanical analysis (TMA) and differential scanning calorimetry (DSC) techniques. The results of mechanical properties showed higher values in the SLM specimens compared with the obtained in the cast specimens. The micrographs revealed a typical morphology of consolidation process, characterized by selected layer used in the SLM technique and the dendrites arms in the casting technique. The thermal results confirm the phase’s transitions of CoCrMo alloy.