Additive Manufacturing of Freeform Ceramic Materials Using Polymer-derived Ceramics (PDC)

摘要

A fast, inexpensive and effective method of manufacturing is introduced in this report. With traditional/subtractive manufacturing used in the manufacturing industry for centuries been labor intensive, time-consuming and material wasting, there is a quest for a more efficient and effective manufacturing method. Recently, another method of manufacturing which solves the problems of subtractive manufacturing was introduced as Additive Manufacturing. Additive manufacturing is the process that builds 3-Dimensional objects or parts by adding layer-upon-layer of material which has its application in plastic, metal and other families of materials including ceramics.;In choosing the best method of manufacturing, it is important to understand the nature of the material and the environment in which it will be applied. There are several methods of additive manufacturing but for the purpose of this research, 3D printing which is a novel and attractive Computer Aided Design (CAD)/ Computer Aided Manufacturing (CAM) build-up technique using various technologies was selected. The part/product is designed on a computer, sliced into layers (G-code) by software and the G-code is transferred to the 3D printer to produce the appropriate parts.;Polymer Derived Ceramics (PDC), are materials with nanostructure resembling that of a polymer and it possesses some ceramic properties. It is a new class of ceramics that can be prepared, without any additives, mostly by the thermal handling of appropriate precursors in an inert/reactive atmosphere or another atmosphere like in an Ultraviolet radiation environment or a thermal environment. The Si-C-N material is a super-material because of its high-temperature stability which encourages its applications in various fields such as medical and health, construction, rapid prototyping, and aerospace industry.;A procedure for manufacturing of ceramic using polymer-derived ceramic was employed for this research and it was established as a success additive manufacturing method which involves the no use of a binder which further highlights the flexibility of this manufacturing method. This method involves technical steps which are paste preparation, extrusion, curing, and pyrolysis. Material selection and mixing are part of the paste preparations while the extrusion process entails forming the material's shape, which must be formed before the completion of extrusion. Also, the correlation between the 3D CAD drawings and the final product must be established. Another great achievement in this research was the manufacturing of a machine to aid the manufacturing processes.;The final product is light in weight and porous with incomplete materials dispersion which was as a result of the lower temperature of pyrolysis employed at this stage of the research. For better mechanical properties, pyrolysis can be done at a higher temperature and also a better method of dispersion such as ultrasonication can be employed.