Study of effect of chemical composition on microhardness parameters of deposited metal by Fe—C—Si—Mn— Cr—W—V alloy

Abstract

Studies of the deposited layer obtained using flux-cored wires of the Fe—C—Si—Mn—Cr—W—V system by introducing titanium and carbon-fluorine-containing material into their composition — gas cleaning dust of aluminum production, wt.%: 21...46 Al2O3; 18...27 F; 8...15 Na2O; 0.4...6 K2O; 0.7...2.3 CaO; 0.5...2.5 SiO2; 2.1...3.3 Fe2O3; 12.5...30.2 CTotal; 0.07...0.9 MnO; 0.06...0.9 MgO; 0.09...0.19 S; 0.10...0.18 P. The deposited layer was obtained using submerged arc surfacing by the ASAW-1250 welding tractor using a fabricated flux-cored wire made from slag produced by silicomanganese with a chemical composition, mass. %: 0.50 FeO; 15.16 MnO; 29.13 CaO; 42.40 SiO2; 6.80 Al2O3;1.39 MgO; 0.18 Na2O; 0.59 K2O; 0.28 S; 0.022 P; 0.004 ZnO; 0.024 C; 0.32 F; 0.17 TiO2; 0.033 Cr2O3. The studies carried out made it possible to establish the relationship between the chemical composition of the deposited flux-cored wire and the structure and properties of the deposited metal. It has been established that the introduction of titanium increases the values of hardness and microhardness. The use of a carbon-fluorine-containing additive leads to microstructural changes expressed in obtaining the structure — ferrite, perlite and bainite, in contras t to the structure — martensite, δ-ferrite and residual austenite, as well as to an increase in the size of martensite needles in the structure of the deposited layer. Microstructural changes are due to the introduction of a carbon fluorine-containing additive into the composition of flux-cored wire and are accompanied by a change in microhardness and hardness. With an increase in the content of the carbon-fluorine-containing additive in the composition of flux-cored wire, an increase in the microhardness and hardness of the deposited metal is observed.