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This paper selected low carbon steel as the skin material, select the amount of Mn powder, Cr powder, Cr 3 C 2 powder, NiAl/NiAl2 intermetallic compounds, FeB powder, FeSi powder , rare earth ferrosilicon alloy powder as a core material made of new cored wire, and steel boiler tubes 20 steel as the base material, the use of supersonic arc spraying technology to prepare for high-temperature coal-fired power plant boiler piping erosion of four kinds FeMnCrNiAlBSi / Cr 3 C 2 Coatings (C1, C2, C3, C4). Through a series of experiments designed to study four kinds of coating methods microstructure, hardness, bonding strength, cohesive strength, thermal shock resistance, high temperature oxidation resistance and high temperature erosion wear performance, using optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) analysis and other methods are discussed. The results showed that the coating showed typical lamellar structure, compact. Coating the solid solution phase composed of oxide phase and porosity. Coating the solid solution phase contains Fe, Mn, Cr, Ni, Al and other elements, which, C3, C4 coating further contains B, Si element. Coating the oxide region contains Fe, Mn, Cr, Ni, Al, O element. Four Coatings showed a higher microhardness, C3 average microhardness of the coating reached 454.5 HV0.1. Four Coatings have high bonding strength, in which the binding strength of the coating C4 11.5MPa; Four Coatings greater than the cohesive strength of 180MPa, wherein the C3, C4, respectively, the cohesive strength of the coating achieved: 246.6 MPa, 258.7MPa, can better meet the actual requirements. The tensile fracture surface coating showed brittle - plastic combination of features, C4 coating dimple obvious. Four kinds of coatings are heat shock 23 times more obvious cracks, 27 or more times before falling off. C4 coating has the best thermal shock resistance. After 100 hours oxidation test confirmed: C1, C2, C3, C4 coating oxidation resistance than steel 20 steel boiler tubes were increased six-fold, 5-fold, 9-fold and 7-fold. Four Coatings are generated surface oxide Fe2O3, Fe composite oxide of Cr, Mn and Al composite oxide; C3 surface of a dense oxide film, and more complete, C3 content of Al in the oxide film highest 20.50At %, C3 interlayer oxide high Cr content, at 18.20At%; Four Coatings degree of oxidation in the order of section C2, C1, C4, C3. Four kinds FeMnCrNiAlBSi / Cr 3 C 2 coatings on impact angle 60 °, the highest rate of erosion, high temperature erosion wear characteristics between the plastic material and between brittle materials. Four kinds of high temperature erosion resistant coating performance was significantly better than 20 steel, which C3 coatings showed the best resistance to high temperature erosion wear. FeMnCrNiAlBSi / Cr 3 C 2 coatings by abrasive extent of the damage was significantly smaller than the 20 steel, high-temperature erosion topography showing the characteristics of the plastic material. Compared to the other three coatings, C3 coating has a dense, homogeneous structure, high bonding strength, cohesive strength and good thermal shock resistance, high hardness, resistance to high temperature oxidation and the best and high temperature erosion wear resistance, thermal power plant boiler tubes can be used as anti-erosion protection coating applications.
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