INVESTIGATION OF THE -EFFECT OF FLYASH ADDITION ON THE MECHANICAL PROPERTIES DIMENSIONAL ACCURACY AND SURFACE FINISH OF GREEN SAND CASTINGS OF Al-11% Si ALLOY

Abstract

With commissioning of new thermal power stations India produces large quantities of flyash which is hazardous waste product. Apart from storage problem, i,t is causing adverse environmental impacts and ecological imbalances in the surroundings areas. Today the major portion of this waste remains unutilized. However, slow acceptance of flyash is due to, restricted level of knowledge regarding its influence on the performance in the foundries and other areas. This work was undertaken to find out the effect of flyash , addition on the dimensional accuracy and surface finish of Al - 11% Si alloy castings made in green sand moulds. The following properties of the castings have been studied (i) Dimensional Accuracy. (ii) Surface roughness. (iii) Volume porosity. (iv) Tensile strength. (v) Impact,strerigth. (vi) Hardness. In general, the flyash additions improve the tensile strength, impact strength, hardness, surface finish and volume porosity. The dimensiional accuracy is improved at higher additions of flyash.