Development of a multi-functional direct laser sintering system

Abstract

One cutting edge technology in rapid prototyping is direct laser sintering of metals and other materials for the fabrication of functional parts and tooling. The most difficult aspects of this technology include the prevention of oxidation of metals during the high temperature sintering, the control of distortion and shrinkage of the materials to achieve the high accuracy and the attainment of full density in the final part. A multi-functional direct laser sintering system has been developed at the National University of Singapore for sintering various materials with high quality. The hardware and software design of the system is described. Accuracy issue is of particular concern in the development of the system and detailed analysis of error sources and technical measures for reducing the errors are undertaken. Three kinds of materials-copper based metal, silica sand and nylon-based plastic, as well as their respective processes, were developed for engineering applications. An application of the system in making inserts for an injection mould is included in this paper to demonstrate the capability of the system. © Professional Engineering Publishing 2004.