Steel surface strenghtening by overlay welding and plastic deformation
Keywords:overlay welding, coating, powder, hardness.
A study of this work was to overlay welding of struc-tural steel by automatic submerge arc welding process with mixtures, consisting powder of high speed steel P6M5 and oxidized titanium chips, milled grinding disks (SiC). Powder of waste materials mixed with manufacturing powder consist of manganese, chromium, nickel, aluminium and other elements were bounded with liquid glass to the base metal and melted by arc struck between continuously supplied low carbon steel wire Cв 08 (<0.1%C, 1.2 mm diameter) under the flux OCЦ 45. Maximum hardening was fixed at 650°C after the heat treatment of coatings at 500–750°C for 1 hour. The higher hardness (54 HRC) was obtained at 600°C temper-ature after the heating for 3 hours and after the plastically deformation – from 27 HRC up to 52 HRC. The structure and properties of coatings were investi-gated by metallographic and X-ray diffraction methods, by measured hardness and microhardness.