| By using dipping enameling on a low carbon steel, the effects of firing temperatures and time on microstructure and properties of a enamel coating were studied, and the decarburized layer thickness of the base metal and the hardness of the enamel coating were measured. The effects of the decarburization of the base metal on bubble formation in enamel coating, the relationship between hardness and firing temperature and time, the effect of crystal nucleus addition and influence of adding adhesive agent in enamel batch on adherence of the enamel coating and base metal were investigated. The acid resistance, alkali resistance, heart-resistance temperature and thermal shock temperature of the enamel coating were measured.Experiment results show that the decarburization layer thickness of the base metal is increased with the increase in temperature and time. The bubble formation in enamel coating is eliminated during the firing the enamel coating after the decarburization of base metal. The adherence between the enamel coating and the base metal by using the length of the interface of enamel coating and base metal with the specific valueηof base metal length to measure. 77 is judge the adherence between the enamel coating and the base metal of important index sign.The hardness of the enamel coating is increased with the increase in temperature and time, and it is improved with the addition of crystal nucleus TiO2. The adherence between the enamel coating and the base metal is improved with the increase in firing temperature and time, and it is enhence with the addition of adhesive agents of NiO and CoO. According to X-ray diffraction analyses, NaAlSi2O6 and Na2Si2O5 appear in the enamel coating. The properties of the enamel coating are as fellows: acid resistance = 94.36 %, alkali resistance = 97.87 %, heat-resistance temperature = 600℃, and thermal shock temperature = 400℃.
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