溶胶-凝胶技术提高不锈钢抗高温氧化及铝合金阳极氧化膜的耐蚀性能

采用溶胶-凝胶法在不锈钢基体表面制备ZrO₂和Al₂O₃涂层，并对铝合金阳极氧化膜进行封孔处理.采用高温循环氧化法研究ZrO₂和Al₂O₃涂层抗高温氧化性能，通过电化学阻抗谱和剥蚀法分析溶胶-凝胶法封孔后铝合金氧化膜的耐腐蚀性能.结果表明:ZrO₂和Al₂O₃涂层的抗高温氧化性能随涂层厚度增加而提高；铝合金阳极氧化膜的耐腐蚀性能也随封孔次数的增加而提高，但当封孔处理超过8次后，阻抗值和腐蚀程度基本不随封孔次数发生变化；实施相同次数封孔处理后，Al₂O₃溶胶的封孔效果略优于ZrO₂溶胶的封孔效果. 

Improvement in the high-temperature oxidation resistance of stainless steel and the corrosion resistance of the anodic oxide films of aluminum alloys by sol-gel technology

A sol-gel method was applied to prepare ZrO₂ and Al₂O₃ coatings on stainless steel(SS304) substrates and to seal the anodic oxidation films of an aluminum alloy. The high-temperature oxidation resistance of as-prepared ZrO₂ and Al₂O₃ coatings was investigated by cyclic high-temperature oxidation tests. The corrosion resistance of the sealed anodic films was investigated by electrochemical impedance spectroscopy(EIS) and exfoliation corrosion method. The experimental results indicate that the high-temperature oxidation resistance of the ZrO₂ and Al₂O₃ coatings is improved with the increasing of coating thickness,and the corrosion resistance of the sealed anodic films is also improved with the increasing times of sealing processes. However,the impedance value and corrosion degree of the sealed anodic films change slightly after more than 8 times of sealing processes. The corrosion resistance of the anodic films sealed with Al₂O₃ sol performs a little better than those with ZrO₂ sol with the same times of sealing processes.