Microstructure and Abrasive Resistance of Glass-Ceramic Composite Coatings from Fly Ash and Al-TiO₂-B₂O₃

Using fly ash and ten percent of Al-TiO2-B2O3 powders as raw materials, the glass-ceramic composite coating was prepared on the substrate of Q235 steel by thermal-chemical reaction method, which was named coating with exothermic chemical system, and its phase, cross section morphology, thermal shock resistance, microhardness and abrasive resistance were studied. In addition, a ordinal glass-ceramic composite coating from fly ash without Al-TiO2-B2O3 as contrastive coating was prepared. The results indicate that some new phases, such as NaB15, TiB2, Na2B4O7 and Ca2Al2SiO7 were found in the coating with exothermic chemical system, and the coating had better bond strength, and its maximum microhardness could reach 700 HV0.1. The number of thermal shock resistance from 700 ℃ to room temperature could reach more than 50 times.Compared with the Q235 steel and the ordinal coating, the abrasive resistance of the coating with exothermic chemical system increased 9.67 times and 0.63 times, respectively.