Tesis

The need of fast production of prototypes of complex shapes in very short time lead to the development in the last years of many additive rapid prototyping [RP] technologies for the production of single objects or of very limited series. Such new fabrication concept allowed the construction of complex parts, starting from a 3D CAD model, without using a mould. However, most of these additive processes produce polymeric objects and only recently ceramic and metallic powders have been processed and employed as raw materials in RP technologies.In the present work the production of composite polymer/ceramic objects by microstereolithography is presented. The suspension is characterized by 55 per cent by weight of powder content and by a reactivity and a viscosity compatible with its application in the stereolithography process. The ceramic green part is built in a microstereolithographic system operating with a non coherent broad-band Hg light source and including a dynamic mask.In addition, a new application of previous system to the production of copper devices is exposed. 88 per cent by weight copper poweder photosensitive suspensions are proposed and optimised for their application to the manufacturing of high density copper parts. Final metallic devices are obtained by pyrolysis of the organic binder and subsequent sintering of the green part at 620 C degrees. Modifications introduced to the conventional microstereolithography machines, for getting it able to process high loaded copper suspensions, are also discussed.