THE EFFECT OF HEAT TREATMENT ON ABRASIVE WEAR RESISTANCE OF Fe-34Cr-4.5C%WT HARDFACING ALLOY

Abstract: Hardfacing is one of the most useful and economical ways to increase the service life of components subjected to abrasive wear. Iron based hardfacing alloys have long been considered as candidate coatings for wear-resistant applications in industry. In the present work two layer of Fe-34Cr-4.5C%wt hardfacing alloy was deposited on ASTM A36 carbon steel plates by SMAW method. The microstructure consists of large primary and eutectic M7C3 carbides, metastable austenite and small amount of secondary carbides. The microstructure was analyzed by optical and scanning electron microscopes. In the same condition of size, shape, distribution and volume fraction of carbides the as-welded matrix changed to martensite, tempered martensite and ferrite by heat treatment processes. The wear resistance was measured by pin-on-disk method under loads of 5, 10 and 20N and for sliding distance of 1500m. The results showed that the as-welded sample with austenitic matrix has the most and the ferritic matrix specimen has the least wear resistance. The predominate mechanisms for mass losses were determined to be micro-cutting, microploughing.