盐和水蒸气协同作用下TiAl合金腐蚀性能研究及其防护

Study of Corrosion Behavior and Protection of TiAl Alloy under Synergistic Effect of NaCl and Water Vapor

研究了在700℃盐和水蒸气协同作用下TiAlNb合金的腐蚀行为以及溅射涂层对TiAlNb合金的防护作用。结果表明。在盐和水蒸气协同作用下,溅射TiAlCrAg涂层对TiAlNb合金具有一定的保护作用。盐和水蒸气协同作用加速了合金以及涂层的腐蚀。挥发性气体氯化物对α2相的循环作用是TiAlNb合金腐蚀的主要原因。涂层中较少的α2相以及Laves相中较高的Cr含量是腐蚀有所减缓的主要原因。

The corrosion behavior of the TiAlNb alloy and the protection effect of the coating axe studied in the presence of NaCl and water vapor at 700℃. The results indicate that the corrosion is severely speeded up when the atmosphere contains NaCl and water vapor. With the temperature increasing,the corrosion accelerates. The TiAlNb alloy exhibits higher corrosion rate than the alloy with TiAlCrAg coating because chloride intrudes into αz phase of the TiAlNb alloy.