| In this paper,different thickness enamel layers were prepared on the surface of38CrMoAl steel using enamel coating technology.The effects of rare earth CeO2 and heat treatment on the microstructure and properties of enamel coating were studied.The wear resistance,corrosion resistance and thermal shock resistance of enamel coatings prepared under different process parameters were compared and analyzed..The results show that:1?At the sintering temperature of 900?and holding time of 45min,the enamel layer with a thickness of 256?m is dense and has no pores,and its surface is smooth.Its surface hardness is720HV0.1.the wear rate is 2.9×10-13m3/N.m.The corrosion resistance rating RP/RA is 10/10 vs B.The thermal shock temperature is 640?.The optimum process parameters of rare-earth CeO2 modified enamel coating are as follows:When the temperature is kept at 870°C for 30 minutes,the optimal CeO2 content is2%.The porcelain surface of the enamel coating treated by the process is smooth,dense and non-porous,the surface hardness is 759HV0.1,and the wear rate is 0.21×10-13m3/N.m.The hardness increased by 5%and the wear rate decreased by 92.8%compared with the enamel layer without adding rare earth.3?The 256?m thick enamel coating prepared by sintering at 900°C for 45min is kept at800°C for 30min and air cooled.The enamel coating is finer and its hardness is 771HV0.1,whichis6.6%higherthanthatbeforeheattreatment.Thewearrateis0.27×10-13m3/N.m,which is 90.7%lower than before heat treatment.The enamel coating prepared by sintering at 870°C for 30 minutes and having an addition amount of 2%CeO2 is kept at 800°C for 30min and air cooled.The enamel coating has fine grain size and uniform distribution,and its hardness is 785HV0.1,which is 3.3%higher than that before heat treatment.The wear rate was 0.18×10-13m3/N.m,which was 14.3%lower than before heat treatment. |
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