AN INVESTIGATION ON MICROSTRUCTURAL AND MECHANICAL PROPERTIES OF CERAMIC MOULDS APPLIED IN THE INVESTMENT CASTING OF CRITICAL PARTS OF AIRCRAFT ENGINES

摘要

The present study is concerned with the investigation of microstructure, mechanical properties and porosity of two types of ceramic moulds designed for precise casting of parts of aviation turbines, the method by lost wax casting, i.e. moulds based on quartz with an alcohol and water binder. The bending strength was determined for model ceramic moulds depending on the annealing temperature. In order to verify the technological quality of casting ceramic moulds, created on the basis of quartz and two different binders, SEM microstructure tests were carried out and the average porosity of casting ceramic moulds was determined using X-ray computed tomography (CT). The results obtained prove that the application in moulding mixtures of water-dispersive binders, it increases the mechanical properties of moulds with definitely better their permeability.