Laser sintering of polyether sulfone/carbon black composite powders using near-infrared laser

Abstract

Low-cost miniaturized laser sintering equipment remains lacking at present; therefore, the development of laser sintering technology and its widespread applications are significantly hindered. Traditional laser sintering equipment is composed of a carbon dioxide laser, water cooling system, powder-box-heating device, and thermal insulation device. Such requirements are the main factors limiting the miniaturization and economic efficiency of laser sintering equipment. Herein, a laser-sintered material was fabricated by sintering using a near-infrared laser light source with a wavelength of 1064 nm without heating, and its microstructure and properties were systematically studied. Polyether sulfone (PES) and carbon black (CB) powders were selected as the raw materials for preparing PES/CB composites by mechanical mixing. For synthesizing the PES/CB composite powders, the CB powder content was varied within the range of 0.25%–1.5%. The PES/CB powders with different component ratios were subjected to laser sintering treatment, and the corresponding microstructural evolutions of the sintered parts were analyzed. The effects of different component ratios on the mechanical properties and dimensional accuracy of the sintered part were investigated, and the optimal content of CB powders of the PES/CB composite material was determined. Additionally, the effects of laser power (10–18 W), scanning speed (1200–1600 mm/s), and scanning spacing (0.04–0.08 mm) on the forming quality of the sintered parts of the PES/CB composite powders were evaluated. The processing parameters of the laser sintering of PES/CB composite powders were explored using orthogonal experimental tests and optimized using the comprehensive weighted method.