Thermal Analysis and Design of Scanned Rapid Prototyping

In thermal rapid prototyping techniques, such as laminated object manufacturing, the distributed quality features of the product, including dimensional tolerances, material structure and mechanical strength, must be monitored and controlled simultaneously by the process conditions. This is ensured by a flexible heat input distribution on successive layers of the prototype, provided by a scanned motion of the heat source. Scanned thermal processing is modeled by a composite simulation, consisting of a numerical description of the solid conduction field with an embedded analytical formulation of the melt flow. This simulation, together with surface temperature measurements by infrared thermometry, is used for a comparative analysis of serial and scanned thermal processing, with the latter resulting in a desirable temperature distribution yielding favorable material characteristics. The model also serves for offline design of the torch trajectory to optimize the 2-D geometry of the processed prototype laminations, and can provide the basis of a real-time controller for various thermal prototyping methods.