Experimental investigation into the selective laser sintering of silicon carbide polyamide composites

This paper presents an experimental investigation into the production of particulate silicon carbide (SiC) polyamide matrix composites via the selective laser sintering (SLS) process. FEPA standard F240 SiC grit was blended with Duraform polyamide to produce a powder blend composition of 50 wt% SiC for direct SLS processing. A full factorial experimental approach was applied to examine the effects and interactions of key fabrication parameters, with regard to the tensile strength and porosity of the composite SLS processed parts. Output from the factorial analyses is presented and discussed and a comparison between the responses obtained for tensile strength and porosity is performed. The effects of incident energy density on the porosity, tensile properties and morphology of the SLS processed parts was also investigated. The optimum energy density for producing parts with maximum strength and minimum porosity was determined experimentally. A further study into the effects of powder blend composition and energy density with regard to tensile strength of composite specimens is also presented. This investigation revealed that the optimum energy density for producing parts of maximum strength was independent of the initial powder blend composition.