THE MECHANICAL EVALUATION OF SHELL MOULDS

摘要

The concentration on process measures during the manufacture of investment casting parts has led to an increase in the number of process variables being regularly monitored. Amongst these the mechanical properties of the shell mould has been one of the measures which for many years has been seen as important, usually in the form of the flat bar 'modulus of rupture' test. The 'modulus of rupture' test requires a number of conditions, including the orientation of the testbar, to be held constant and these will be defined by the foundries or shell manufacturers undertaking the evaluation. However, these conditions are not necessarily the same between the different organisations. Some of these differences will be evaluated and the logic for choosing different configurations will be developed. The mechanical evaluation of shell moulds was undertaken and the resultant mechanical strengths analysed. There is comparative between different methods of evaluating the shell strength and this is reviewed the light of subsequent shell performance.