EFFECT OF FLYASH ADDITION ON MECHANICAL PROPERTIES OF CASTING PRODUCED BY GREEN SAND MOULDING PROCESS

Abstract

Green sand moulding is one of the oldest moulding process ever known to human being It is still most popular and widely used casting process because of it's greater flexibility as a production process and least costly method of moulding. 'Around 60% of sand aggregate goes as waste after the casting solidification .Flyash, which is ejected out of thermal power plants as waste material, has been used as an additive to silica sand in the proposed work. The use of flyash reduces the cost and on the other hand it improves the solidification rate. The objective of the present work is to visualize the effect of flyash addition on the mechanical properties of Al-7% Si alloy castings produced by green sand molding process. This alloy normally has excellent castability property.This alloy has the advantage of being heat treatable.The alloy finds its application in aircraft pump parts, aircraft fittings, water cooled cylinder blocks, cylinder heads, wheels etc. The Taguchi technique has been used to plan the experiments.The experiment works carried by using L27(313 ) OA.. The main effects of flyash and other process variables such as percentage bentonite mixed, percentage of water in the sand aggregate and pouring temperature of alloy on the mechanical properties of the Al-7% Si alloy castings have been plotted . The results show that tensile strength and percent elongation reduces with increase in percent flyash added to silica sand while hardness increases with increase in percent flyash added to silica sand