渗铝镍基高温合金热腐蚀行为研究

采用低压气相渗铝工艺制备铝化物涂层 ,在涂层表面涂敷不同NaCl+Na2 SO4 含量的熔盐进行 90 0℃热腐蚀实验 .结果表明 ,涂层对NaCl含量不敏感 ,这与涂层表面生成Al2 O3 氧化膜有关 .涂层能有效提高合金抗热腐蚀性能 .     

Na_2SO_4- and NaCl- Induced Hot Corrosion Behaviors of a Nickel-Base Superalloy with Aluminide Diffusion Coating

Hot-corrosion behaviors of nickel-base superalloy and aluminide diffusion coating have been investigated in conditions of contents of Na2SO4 and NaCI molten salts at 900℃ by means of XRD and SEM. Hot-corrosion scale of the superalloy and aluminide diffusion coating were analyzed and their surface morphologies were observed. The results demonstrate that both coated and uncoated specimens are not susceptible to various contents of NaCI. That may be resulted from the AI2O3 scale formation. Growth stress was characterized by the formation of convoluted scales.