Abstract: A method and apparatus for directly making rapid prototype tooling from a computer model having a free-form shape. The method steps comprise essentially: (a) machining a soft metal tooling base so as to contour at least one free-form surface in conformity with the computer model; (b) cold-gas dynamic spraying the contoured surface to form superimposed impact welded metal particle layers, the layers consisting of at least one thermal management under-layer comprising primarily copper, and at least an outer wear resistant layer comprising primarily tool steel.

Abstract: A method for quantitatively predicting and consequently minimizing the amount of critical phases such as eutectic Al2Cu formed during solidification of Al—Si—Cu alloys used in a vehicle engine component comprises developing a micromodel to simulate microstructure evolution in cast Al—Si or Al—Cu alloys. The micromodel is calibrated using experimental thermal analysis cooling curves and an optimization process. Microstructure evolution and cooling curves are simulated for a casting using the calibrated micromodel. Precipitation of critical phases such as Al2Cu in the casting is predicted as a function of solidification conditions. The model allows casting process variables to be varied with predictable results so that the casting process can be controlled via the micromodel.