Direct laser sintering of Cu-based metal for rapid tooling

Direct laser sintering of metals, as one of the important trends in Rapid Prototyping (RP) technologies, is discussed in this paper. A high-temperature direct laser sintering system has been developed for the sintering of Cu-based parts to be used in making metal moulds for rapid tooling. To be successfully sintered at a relatively low temperature, a special Cu-based alloy material has to be developed. Experiments on the direct laser sintering of the Cu-based metal were conducted to identify optimal parameters and conditions for building three-dimensional metal parts. The mechanism of laser sintering of this material was disclosed by the SEM analyses of microstructures of the sintered parts and other characterisation analyses. The density, surface roughness and mechanical properties of the laser-sintered parts according to the variation of process parameters were measured and analysed. The effect of process parameters to the accuracy of sintered parts was also investigated. On the basis of the experimental study, the developed material and process was successfully applied to build a pair of Cu-based inserts for an injection mould.