Selective laser sintering of acrylonitrile butadiene styrene polymer and post-processing enhancement: an experimental study

Acrylonitrile butadiene styrene (ABS) polymer refers to a high-molecular-weight amorphous copolymer with a wide softening range and specific viscoelasticity of polymer material. The application of such powder materials in additive manufacturing technology for selective laser sintering (SLS) for forming and its post-processing enhancement are rarely investigated. In this paper, the standard specimens of ABS powder were fabricated by SLS. The dimensional accuracy and the mechanical properties of specimens were examined, and the microstructure of tensile fracture was observed under a scanning electron microscope (SEM). The tensile, flexural, and impact strengths were obtained as 2.44 MPa, 5.10 MPa, and 2.77 kJ/m2, respectively, as indicated by the results of this study. Accordingly, the SLS ABS parts are not suitable as functional prototypes. According to the thermodynamic equation, dissolution equation, capillary permeability formula, and the selection of diluent, the influence of diluent on viscosity, the influence of curing time on viscosity, and the influence of curing agent and viscosity on permeability are studied. Thus, the parts were infiltrated with two different types of epoxy resin (system Y and system W) to enhance the mechanical properties. The mechanical properties of specimens administrated with curing agent W increased 4.57, 3.87, and 1.64 times in terms of tensile, flexural, and impact strength, respectively; the others administrated with curing agent Y increased 6.38, 3.52, and 1.05 times, respectively. Accordingly, the results indicate that the SLS ABS parts enhanced by epoxy resin can serve as function parts, which is a feasible method since the properties of the composites can be readily tailored by changing different infiltration resins.