INVESTIGATIONS ON MODIFICATION OF BINDER SYSTEM IN INVESTMENT CASTING

Abstract

Investment casting process has been extensively used for ages. This process is also known as ‘lost wax casting’ or ‘precision casting’. This casting process can produce extremely complex products with good dimensional accuracy and excellent surface finish. Due to environmental and economic pressure there is a need to improve casting quality and reduce manufacturing cost. Poor quality of the slurry ingredients lead to the poor quality of the casting. During dewaxing process, small cracks are likely to be developed in the ceramic shell because of the wax expansion and the poor mechanical properties of the shell. These cracks can be reduced by modifying the slurry ingredients. In the present work, an attempt is made to improve the strength of the ceramic shell. Fevicol was mixed with the binder of conventional slurry ingredients. Fevicol was added to the inner coat of the shell. It has a good binding property. Ceramic shell was prepared using both the slurries. Slurry and stucco retention property was measured for both shells. The addition of fevicol has improved the retention property of the shell as compared to the conventional shell.