Research Of High Frequency Induction High Chromium Cast Iron Cladding Coating On The Surface Of Q235Steel

Induction cladding technology is a new surface treatment technology developed in recentyears, and it has a very broad application prospects in industrial technology and other fields.On account of wide raw material sources, low price, good performance, at room temperatureand below400℃it has good abrasion resistance and weak corrosive Fe-based alloy powderis widely used, while the Fe-based high chromium cast iron alloy is a kind of goodwear-resistant material, it has more than the general white cast iron with high toughness andstrength, but also it has good resistance to high temperature and corrosion, and because of itsconvenient production, low cost, it is regarded as the one of the most excellent resistance toabrasive wear of materials. Cladding coating wear-resistant materials in low carbon steelsurface, not only could retain the good plasticity and toughness of low carbon steel, but alsogreatly improve the surface hardness and wear-resistance of the material, prolong the servicelife of the workpiece. In this paper, high chromium cast iron cladding coating was preparedthrough high-frequency induction cladding technology in low carbon Q235surface, and thenmade a preliminary analysis in Microstructure and mechanical properties of the claddingcoating.In this paper, the binder which about induction cladding was selected at first,the optionaladhesive were sodium metasilicate, polyvinyl alcohol, phenolic resin, experimental resultsshowed that sodium metasilicate was the best as binder, after drying, the surface of alloypowder was smooth, and the substrate sample without stripping. Then the induction claddingprocess parameters and the cladding after the end of the cooling process were optimizedselected, when concussion current was50A,60A,70A,80A,90A,100A,cladding coatingprepared by macroscopic observation and microstructure observation, and concluded that thecurrent for90A shock when cladding effect was most ideal; through the cladding after theend of cladding coating water cooling and air cooling treatment contrast, obtained that theeffect of water cooling is better than air cooling. Then the coating of four groups of differentCr content in the alloy powder were prepared, and the microstructure, phase and mechanicalproperties of the cladding coating before and after heat treatment were analysed, the claddingon Microstructure and mechanical properties were compared, obtained the content of Cr was20%when the quality of cladding coating was preferable, and microhardness and macrohardness was the highest, the hardness of cladding coating about content of20%and15%forCr increased slightly, the hardness of cladding coating about content of25%and30%for Crdecreased.The cladding coating on the content of20%for Cr was measured with XRD, alarge number of blocks, strips of eutectic distributed in the cladding coating on the surface ofradial organization. Organizations are mainly in the martensite C_0.14Fe_1.86and γ-（Fe, Cr,Ni, C） alloy solid solution phase as well as the hard phase （Fe, Cr）₇C₃and Fe₅Si₃intermetallic compounds. At last, layers（three） of high chromium cast iron cladding coating was prepared, thethickness of first layer was about1mm, the second is about2.5mm,the third was about3.5mm,the microstructure and properties of cladding coating were uniformly dense,there were notimpurities and defects such as shrinkage hole, the cladding coating and the Q235matrix weremetallurgcally combined. As the detection of XRD, the numbers of carbide Cr₇C₃andmartensite phase C_0.14Fe_1.86on the surface of cladding coating about the thirst layer werehigher than the single cladding coating. From the hardness distribution curve it informedthat,within a certain range, with the cladding coating thickness increased, the surfacehardness of cladding coating increased, the surface hardness could reached62.28HRC in thethird layer of cladding coating.