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Reports that measurable amounts of polymer degradation occur during the fabrication of objects from polymer coated ceramic powders by selective laser sintering (SLS). Argues that because the binder is important in achieving strong green parts that can be handled with minimal breakage during post‐processing operations, it is essential to minimize the extent of binder losses. As the first step towards understanding the mechanisms of binder degradation, this paper presents a thermal model of the physical system, noting that the agreement between theory and experiment are good. The model is used to help determine the most influential parameters affecting binder losses during fabrication from polymer coated powders. Predicts that adjustments to laser beam diameter, laser scanning distance and gaseous environment will strongly affect polymer binder degradation during processing. Further predicts correctly that polymer degradation during SLS processing is not sensitive to the inherent degradation kinetics of the polymer.

Presents the mechanical properties of a new mould‐making material, proposed for producing rapidly prototyped injection mould inserts for plastics by selective laser sintering. Explains that although the strength of this material is far below that of the tool steel usually used to fabricate moulds, design calculations indicate that it can still be used for mould insert production. Points out that the thermal conductivity of this material is lower than that for steel but higher than that for plastic melts. Indicates from the calculations that proper choices of conduction length and cycle time can minimize differences, relative to steel moulds, in the operational behaviour of moulds made of the new material. Discusses the longevity of example moulds.