Experimental Studies on Microstructure Evolution and Macro Segregation during Upward Directional Solidification of Lead-Tin Alloys

摘要

Directional solidification experiments were carried out on hypoeutectic and hypereutectic Pb-Sn alloys. Different combinations of growth rate V and composition Co. were used to investigate their effect on longitudinal macro segregation. Macro segregation along the length of the samples was observed in hypoeutectic Pb-Sn alloys whereas no such macro segregation was observed in hypereutectic alloys. The intensity of longitudinal macro segregation was found to increase with the increase in initial tin content of the alloy, increase in distance from the chill end and decrease in the solidification rate.