South African Journal of Industrial Engineering
On-line version ISSN 1012-277X
PEREIRA, M.F.V.T.; WILLIAMS, M. and DU PREEZ, W. B.. Application of laser additive manufacturing to produce dies for aluminium high pressure die-casting. S. Afr. J. Ind. Eng. [online]. 2012, vol.23, n.2, pp. 147-158. ISSN 1012-277X.
A number of laser additive manufacturing (LAM) technologies can produce fully-dense metal components that potentially offer opportunities to apply the technology in die or mould making (known as rapid tooling). From these LAM technologies, three were selected for evaluation of their suitability as die cavity inserts in the manufacture of high pressure die-casting (HPDC) dies. Apart from comparing the different LAM inserts with one another, their performance was also compared with components manufactured in a standard hot work steel. In the HPDC process, the die is unique to each component to be produced. Die cavities in particular are subjected to demanding conditions, such as cyclic heating caused by the introduction of molten aluminium at over 650°C, followed by cooling in water-based die release medium at temperatures around 25°C. Besides cyclic heating, the die cavities are also exposed to pressures exceeding 1500 MPa during the injection of molten aluminium into the cavities. This application of LAM, therefore, poses extreme challenges to the technology. The results of this study confirmed that the metals used in some of the LAM technologies did indeed meet the demanding requirements of the current application, and can lead to significant time- and cost-saving during product or process developments. Based on these findings, a number of recommendations are made for users interested in the application of LAM to produce die cavities.