Optimum manufacturing parameters in selective laser sintering of PA12 with white cement additives

Abstract

Selective laser sintering (SLS) is a modern rapid prototyping method with which 3D objects with complex geometries can be manufactured precisely through the sintering of powders’ thin layers using the laser power. The effective manufacturing parameters in SLS are laser power, scanning speed, scan-spacing, and the part-bed temperature. In this work, selective laser sintering (SLS) is used to manufacture a composite material from white cement additives and polyamide 12 (PA12) and then, the influence of energy density (controlled by laser power, scanning speed, and scan-spacing) on the dimensions, density, mechanical properties, and morphology of sintered specimens is investigated. The criteria for obtaining optimum manufacturing parameters are the part dimensional accuracy, maximum density, and maximum strength. Hence, the optimum energy density for producing parts with maximum density and enhanced strength has been determined experimentally. The tensile, compressive, and flexural testing methods are used to evaluate the effects of laser power on the fabricated parts. The results show that the optimum energy density of 0.051 J/mm2 could achieve the highest density of sintered parts without any degradation of binder material. Also, it is found that a combination of a 0.051-J/mm2 energy density and 10% weight fraction of white cement is sufficient enough to enforce significant improvements on the mechanical properties of PA12-sintered specimens.