Abstract: In the roll welding composite manufacture, in order to save precious carbon, improve cost-effective of hardfacing material, the submerged arc welding of flux-cored wires is used while the deposited metal remained unchanged in order to research the influence of different carbon, chromium adding ways to deposited metal microstructure and properties. Through the abrasion hardness, high tensile, high room temperature toughness and quantifying the amount of wear of the sample before and after, the relationship between microstructure, adding ways and wear resistance is analyzed combining the microstructure before and after wear, scanning electron microscopy and other aids. When Cr5 series hardfacing alloys are used, on the basis of keeping the compositions of hardfacing deposited metal unchanged basically, it is researched about the influence of different addition ways of carbon and chromium on microstructure and properties of hardfacing alloy. The results show that the high-temperature wear resistance of hardfacing metal is proportional to the high-temperature strength and hardness of the alloy at the temperature of 600℃, and improved along with the increase of alloy toughness; for the flux-cored wire with direct addition of graphite and chromium powder, the wear resistance of hardfacing deposited metal is much better than that with direct addition of chromium carbide. High-temperature wear results from multiple factors including alloy oxidation, cutting, fatigue cracking and stripping, etc. Ideal high-temperature wear-resistant hardfacing material depends on not only the alloying system adopted by hardfacing metal, but also other factors such as microstructure, anti-oxidation property, high-temperature strength and toughness. Therefore, changing the addition way of alloys may strengthen deposited metal without need of modifying agents and external field excitation.

Key words: Cr5 series alloy, Hardfacing, Roll, Wear resistance