Characterisation of powder and microstructure, density and surface roughness for additively manufactured stent using medical grade ASTM F75 cobalt chromium (CoCrMo) by selective laser melting (SLM) technology

Abstract

ABSTRACT This paper explains and demonstrates the capabilities of Metal Additive Manufacturing (MAM) technology in producing intricate stent structure with a customise design by using ASTM F75 Cobalt-Chromium (CoCrMo) powder. Current commercialise stent in the market is rigid in size and geometries and the cost of tooling and manufacturability are increased once the other stent production is replaced. The design, process parameter, powder characterisation, part density and microstructure were investigated and thus exploring the potential area of MAM process for future proof stent manufacturing. Average density achieved for the seven (7) additive-manufactured stents was within 92– 97%, whereas the shrinkage is in between 0.31% and 0.61% (diameter) and 0.03–0.05% (height) respectively. The average surface roughness achieved are 4.1 µm (highest peak) whereas the lowest peak was 365.1 nm. The suggested model of the stent was taken from the third-party vendor and fabrication was carried out using EOSINT M280 metal printer with the aid of Materialise Magics 19.0 software for support generation.