The Production of alloyed white cast iron for the use in the crushing and grinding operations in Sri Lanka

Abstract

This thesis· describes the work that have been carried out to produce different types of cast iron grinding media and liner plates of good wear resistant quality for the local industry. The types produced ,.,ere lm·r chromium, nickel chromium, martensi tic and high chromium ,.,white cast irons. The castings \·.'ere carried out at the Ceylon Steel Corporation ,.,hile the micro structural examination and mechanical testings were conducted at the University of Moratuwa • At present lm·1 alloyed cast steel grinding balls and Hadfield steel liner plates are produced at the Ceylon Steel Corporation for local use and they are found to contain defects ranging from shrinkage cavities, · sand fusions, blow holes, quench cracks to misruns. It is possible to eliminate most of these defects with certain types of alloyed white cast iron. The grinding balls and liner plates so produced showed greater resistance to wear and the casting yield ,.,as higher when compared with the castings of balls and liners. Although the price of alloyed white cast iron is marginally higher than the. cast steel balls and Hadfield liners, the longer life of the 'former more than compensates the replacement of c-ast steel balls, Lindfield liners with the white cast iron halls and liners.