Valuation of mechanical properties and microstructural characterization of ASTM F75 Co-Cr alloy obtained by Selective Laser Melting (SLM) and casting techniques

Abstract

Advances in processes using the powder metallurgy techniques are making this technology competitive compared to the other traditional manufacturing processes, especially in medicine area. The additive rapid prototyping technique – selective laser melting (SLM) was applied in a biomaterial of CoCrMoFe alloy (ASTM F75), to study the mechanical properties and microstructural characterization in comparison between the conventional technique – casting. The gas atomized powder was investigated by their physical (as apparent density, bulk density and flow rate) and the chemical properties. The powder was analyzed using scanning electron microscope with energy-dispersed X-ray spectroscopy (SEM-EDS) and X-ray fluorescence. Specimens of standard samples were manufactured using these techniques to evaluate the mechanical properties as uniaxial tensile (yield strength, rupture tensile and elongation), transverse rupture strength and the micro hardness. The mechanical properties showed higher values in the SLM specimens than the casting specimens. Before the mechanical tests the specimens were examined using optical microscope (OM) and SEM-EDS. The micrographs revealed a microstructure with finer morphology in the SLM technique and the dendrites in the casting technique.