Purpose: The purpose of this paper is to report on a study of the movement of the powder bed material during selective laser sintering (SLS) of bisphenol-A polycarbonate (PC) powder and its effect on the morphology of the sintered specimen.
Design/methodology/approach: Two sintering experiments, i.e. single-spot laser sintering and raster-scan laser sintering, were carried out and the material movement mechanisms were investigated in situ and subsequently by scanning electron microscopy.
Findings: During the raster-scan laser sintering process, the movement of the powder was found to be primarily perpendicular to the scanning direction. When sintering at a high laser power, it significantly affected the surface morphology of the sintered specimens and parallel surface bands occurred along the scanning direction.
Research limitations/implications: Experiments were carried out on a modified laser engraving machine rather than a commercial SLS machine.
Practical implications: A schematic model of the material movement mechanism for each of the sintering strategies is presented.
Originality/value: The results further the understanding of the sintering behaviour of the powder bed.
- Stress (materials)