溶胶凝胶法制备金属基γ-Al_2O_3活性涂层的研究

Investigation on Preparing γ-Al_2O_3 Active Coating on Metal Substrate with a Sol-gel Method

用磷化和溶胶 凝胶技术在Fe Cr Al Y合金材料表面制备活性γ Al2O3涂层,实验确定了合适的磷化温度、磷化时间和涂覆溶胶中Al2O3浓度;分析了涂覆溶胶中添加剂ST(自制)含量及涂覆次数对活性涂层与基体结合力的影响。结果证明:预先在载体表面形成一层磷化膜以及添加含量不超过0.03%的无机组分ST均可以获得高结合强度且活性组分均匀分布的涂层。

The technology of phosphating and solgel was used to prepare γAl2O3 active coating on FeCrAlY material for the catalytic metal support in the automobile exhaust gas purifying system. The correct phosphating temperature , time and the concentration of the Al2O3 in the solution had been decided. The influence of inorganic additive ST(made by ourselves) and coated numbers on the adhesive strength of the coating was explained on the basis of the change of coating weight in the cycles of the thermal impact at elevated temperature. The morphology of γAl2O3 active coating was measured by scanning electron microscope (SEM) and the circumstances of the coating peeling off from the substrate were discussed simultaneously. The experimental result proved that the binding strength of the active component on the metal support was improved with the prephosphating on the metal support and inorganic additive ST in the sol.