Design of experiments as an instrument for development of silicon carbide ceramics with tailored properties

In past decades design of experiments and simulation analysis have been recognised as powerful tools for resource efficiency improvement in various areas of technics and technology, especially for energy-consuming industries such as ceramics production. Silicon carbide ceramics is widely used for structural applications, yet production of such materials invokes high temperatures and sintering aids, thus it becomes an important task to carefully adjust ceramics compositions and methods of manufacturing. Promising sintering aids for SiC including both oxide and non-oxide systems have recently been extended to metals and alloys, Invar-type precision alloys in particular. The present paper discusses the correlation between mechanical behaviour (dependent variable, calculated as single contact strength) and process parameters (independent variables), namely sintering aid content and preparation technique (dry or wet ballmilling), green body pressure value, and ceramics firing temperature for SiC-based compositions with ferrous metal dopants corresponding to NILO and Kovar alloys respectively. The research was carried out within the framework of a full-factor experiment where each independent variable had only two possible values (maximum and minimum), and regression models for SiC-NILO and SiC-Kovar ceramics were constructed. Despite seeming similarity the investigated systems presented completely different responses: significant variables (sorted by relevance) for SiC-Kovar ceramics were firing temperature, sintering aid content and preparation technique, while for SiC-NILO ceramics these were green body pressure value ceramics firing temperature. © SGEM 2017 All Rights Reserved