Chromate-free ceramic composition with reduced cure temperature

Hexavalent chromium free slurries are provided that enable full curing at temperatures as low as 330 DEG F to 450 DEG F, making the coatings particularly suitable for application to temperature sensitive matrix materials. The slurry is suitable for producing a protective coating system formed from a novel silicate-based undercoat and sealed with a novel phosphate-based topcoat. The coating system shows acceptable corrosion resistance and heat resistance and can replace a traditional chromate-containing coating system. 提供了能够在低至330℉至450℉的温度下实现完全固化的无六价铬浆液，从而使得涂层特别适用于施加到温度敏感性基体材料上。该浆液适用于生产由新型基于硅酸盐的底涂层形成并用新型基于磷酸盐的顶涂层密封的保护性涂层体系。该涂层体系表现出可接受的耐腐蚀性和耐热性，并且能够替代传统的含铬酸盐涂层体系。