EFFECT OF ZIRCONIA AND ALUMINA REINFORCEMENTS ON WEAR PROPERTIES OF AL-5%SI ALLOY CAST USING VERTICAL CENTRIFUGAL CASTING

Al 5%Si alloy was reinforced with zirconia and alumina respectively and casts were obtained at 300, 400 and 500 rpm of the vertical centrifugal casting machine. Specimens were cut from both the top and bottom regions of these casts. The specimens were flattened with an emery paper and were subjected to wear tests on pin on disc machine (tribometer). The track diameter was set to 100mm, with a load of 1kg and the tests were carried out for 20 min each. The wear vs. time graphs were obtained for each specimen tested and the specific wear rate was calculated. It was observed that the specimens from the top of the casts experienced the highest wear rates as compared to the specimens cut from the bottom of the casts. Also, Al-5%Si alloy with Zirconia reinforcement was found to experience the least wear rate as compared to Al-5%Si alloy with alumina reinforcement and Al-5%Si alloy with no reinforcement.