The influence of ceramic fibre on thermal expansion of moulding materials for investment casting technology

The results of dilatometric measurements presented in the paper are a supplement to the investigations concerning broadening the composition of ceramic slurry intended for investment casting technology with ceramic fibre matrix. An applying of fibre material and a change of rheologic characteristics of ceramic slurry have impelled to develop the method of applying the material to the pattern sets. The technology of multi-layer spraying has been found to be the most favourable method. Partial replacing of the grain silica materials with aluminosilicate materials in the fibrous form has affected the magnitude of dimensional changes taking place during the heating process. In order to determine the magnitude of these changes, there have been prepared slurries of various fibre fraction in the matrix and their thermal expansion has been examined within the temperature range of 273-1273 K.