316L不锈钢基体氧化铝涂层的氢渗透性能

Hydrogen Permeation Properties of Alumina Coating on 316L Stainless Steel

在316L不锈钢上采用金属有机化学气相沉积（MOCVD）法沉积了氧化铝涂层。使用XRD、SEM分析氧化铝涂层的物相和微观形貌,采用气相氢渗透装置对涂层氢渗透行为进行表征。结果表明,973 K退火处理后涂层为非晶氧化铝,涂层均匀、完整,厚度为190 nm。氧化铝涂层的氢渗透压力指数为0.56~0.78,说明氢渗透过程机制为表面过程和体扩散过程共同控制。氧化铝涂层的表观氢渗透率为P=1.99×10-6exp（-117×103/RT）mol/（m.s.Pa1/2）。氧化铝涂层的氢渗透激活能为117 kJ/mol,远高于316L不锈钢的66.6 kJ/mol,涂层对氢的渗透具有明显的阻挡作用。此外,在873~973 K氧化铝涂层对316L不锈钢的氢渗透阻挡因子（PRF）为59~119,涂层氢渗透阻挡性能优异。

Alumina coatings were deposited on 316L stainless steel by metal organic chemical vapor deposition（MOCVD）.The phase and microstructure of coatings were examined by XRD and SEM,and the hydrogen permeation behavior of coating was measured by a gas-phase hydrogen permeation apparatus.The results show that the alumina coating is amorphous after thermal annealing at 973 K,and the coating is smooth,intact and 190 nm of thickness.The hydrogen permeation pressure exponents of the coating are 0.56-0.78,which indicates the hydrogen permeation of coating is surface and diffusion limited.The apparent hydrogen permeability of the coating is P = 1.99×10-6exp（-117×103/RT） mol/（m.s.Pa1/2）.The permeation activation energy of the coating is 117 kJ/mol,which is much higher than that of 316L stainless steel with value of 66.6 kJ/mol.Thus,the alumina coating effectively suppresses the hydrogen permeation in 316L.Furthermore,the hydrogen permeation reduction factors（PRF） of the alumina coating on 316L are 59–119 at temperatures 873–973 K,and the alumina coating offers excellent hydrogen permeation suppression performance.