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various direct and indirect RT techniques, which use advanced computer-aided techniques and computer-controlled machines to produce nonferrous tooling. The authors performed and made comparisons among three approaches—selective laser sintering ~SLS!, stereolithography ~SLA!, and high-speed computer nu-merical controlled ~CNC! milling—in terms of tool life and tool development cost and time, which can serve as a criteria for the selection of a RT process. Walczyk and Hardt @6 # developed the profiled edge lamination ~PEL! tooling method, in which contoured-edge lamination members are stacked side-by-side and reoriented to a vertical plane, solving the stair-stepped surface problem. Compared to CNC machining, the PEL method elimi-nates most tooling accessibility problems, reduces limitations on die geometry, and allows for faster fabrication. One of the techniques that has been drawing attention from industry recently is the application of aluminum trihydrate~ATH!-of them involve computer-aided techniques with the common goal of reducing development time and cost by replacing full-scale process trials with computational simulations. Numerical simula-tion and modeling of metal forming processes, based on the knowledge of underlying process mechanics and validated by ex-perimental results, are powerful tools for optimizing process pa-rameter