溶胶-凝胶法制备Al_2O_3涂层及对Ni的高温防护

Preparation of Al_2O_3 Coating by Sol-Gel and Its Protection for Ni at High Temperature

采用溶胶-凝胶法以异丙醇铝为原料在Ni基体上制备了Al2O3涂层.用扫描电子显微镜(SEM/EDS)对涂层的表面形貌和化学成分进行了分析.采用热重分析(TGA)研究涂层对金属Ni在900℃空气中高温氧化动力学行为的影响,采用SEM对涂层的表面和截面形貌进行了表征.结果表明:制备的Al2O3涂层完整,在900℃空气中Ni的抗氧化性得到提高.

Al2O3 coating was prepared on nickel matrix by Sol-gel processing of using aluminium isopropxide as precursors. The surface morphology and chemical composition of the alumina coating were in- vestigated by SEM/EDS. The thermal gravimetric analysis was employed to study the effect of the present alumina coating on the kinetics of pure Ni in air at 900℃. The surface and cross sectional morphologies of the blank and coated Ni after 24 h oxidation at 900 12 in air were characterized by SEM. As a result,the Al2O3 coating was uniform and promoted the oxidation resistant of Ni at 900℃ in air.