SOME STUDIES ON ENHANCEMENT OF WEAR RESISTANCE THROUGH ELECTRODE MODIFICATION

Abstract

In the present study, shielded metal arc welding were produced for Fe-20Cr-3C-xB coating and mild steel plates were surfaced with single-pass bead on plate welds. The results of studies carried out on the microstructure, microhardncss, and wear properties of hardfacing alloys deposited on mild steel plate. Wear resistance is measured by the pin on disc tribo test. FESEM and EDAX equipments used for the microstructure analysis of hardfaced surface. Vickers hardness test performed to measure the microhardness. As increase in the boron content the intermediate and terminal phases can be seen. Measurement of microhardness shows variation of hardness from 612 HV05 to 956 HV05 i.e. average reading of hardness across the diagonal on the hardfaced surface also measured hardness with respect to the depth which shows continuous decrease in hardness when moves towards base metal from hardfaced surface. Variation of boron percentages shown that microstructure of the hardfacing has included carbides and formation of austenite and eutectic structure to primary Fe213 with the eutectic of Fe213 plus martensite. From SEM images of worn out surface it can be predict that wear mechanism like microcutting, wedge fbrmation, continuous and discontinuous plastic deformation and chances of crater, because crack propagates from the craters.