| React flame spraying (RFS) is the combination of the self-propagation high temperature synthesis and the traditional thermal spray and the coating prepared by RFS still exists some defects, such as low bond strength, porous microstructure. In this study, Mo2FeB2 ternary boride cermet coating was deposited on Fe substrate by react flame spraying and the induction heating was chosen for the purpose of improving the combination property of the coating.The effects of induction heating for 13 seconds on the phase composition, microstructure, interfacial microstructure, bond strength, microhardness and wear resistance of the Mo2FeB2 coating were studied respectively and the as-sprayed Mo2FeB2 coating was added for the study mentioned above (Two coating samples were mentioned, which one is called as-sprayed coating, the other is called heat treated coating for 13 seconds of induction heating treatment.). X-ray diffractometry (XRD) was used to characterize the heat treated coating, combined with the XRD result for the as-sprayed coating already produced by other researchers; In order to realize the effect of induction heating on the microstructure and interracial microstructure of the coating clearly, one coating sample for 10 seconds of induction heating treatment was introduced together with 13 seconds heat treated coating and the as-sprayed coating. Then scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) were applied to test the effect of induction heating for the three coating samples. The bond strength between the coating and Fe substrate was measured with the pull-off test according to the corresponding GB 8642-88; Micro-hardness of both coating was tested by HVS-1000; Wear resistance of both coating was also analyzed by some equipments, such as polishing machines. The results are as follows:(1) The phase composition of the heat treated coating was unchanged and composed of matrix phaseα-Fe and horniness phase Mo2FeB2 just as the as-sprayed coating.(2) The time of induction heating treatment greatly affected the microstructure and interfacial microstructure of the heat treated coating which became more dense and compact and no obvious element diffusion was found at Ni60/Fe interface for those coating samples.(3) The average bond strength of the heat treated coatings reached 60.48MPa while the average bond strength of the as-sprayed coatings was only 13.1MPa.(4) The average microhardness of the heat treated coating was 1500 HV0.1 while the as-sprayed coating was 1500 HV0.1. The heat treated coating had a strong wear resistance with a rate of wear 0.8 mg/mm2, while the as-sprayed coating just had a normal wear resistance with a rate of wear 1.2 mg/mm2.
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