Microstructures and wear resistance of hardfacing alloy containing internally produced carbide particulates

A new hardfacing alloy was fabricated and deposited on the low-carbon steel Q235 by shielded manual arc welding.The average degree of hardness,microstructure and chemical composition of the alloy were analyzed with the hardness gauge,optical microscopy,scanning electron microscopy and the EDAX pattern,and the abrasive wear resistance of the alloy was also tested.The results show that the microstructure of the alloy is the mixed martensite and little retained austenite with(NbCrTi) C particles which are dispersive distributed in the matrix.The amount of low-carbon and high-carbon martensite is identical,and the hard carbides which have strong metallurgic bonding with the matrix are hold in the matrix effectively.The hardness of the alloy is up to 57 HRC,which is 3.6 times more wearable than that of D707 tungsten carbide electrode.