Abstract The pitting corrosion and surface modifications of aluminium alloy AA2050-T8 (Al-Cu-Li) resulting from immersion in 0.1 M NaCl at open circuit potential were studied by time-of-flight secondary ion mass spectrometry (ToF-SIMS). ToF-SIMS chemical mapping showed a local distribution of chlorides and hydroxides in the pits enriched in Cu and Fe. Preferential sites of corrosion initiation were evidenced in the alloy matrix close to Al-Fe-Cu-Mn intermetallic particle. A formation of an oxide-hydroxide layer with different composition and/or higher thickness was evidenced over IMP than the alloy matrix. LiO dissolved from the oxide layer but metallic lithium was still present in the matrix.

中文翻译：

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对Al-Cu-Fe-Mn金属间化合物颗粒诱发Al-Cu-Li合金点蚀的见解

摘要 采用飞行时间二次离子质谱法（ToF-SIMS）研究了铝合金AA2050-T8（Al-Cu-Li）在开路电位下浸入0.1 M NaCl中产生的点蚀和表面改性。ToF-SIMS 化学图谱显示在富含 Cu 和 Fe 的凹坑中局部分布着氯化物和氢氧化物。在靠近 Al-Fe-Cu-Mn 金属间化合物颗粒的合金基体中证明了腐蚀起始的优先位置。与合金基体相比，在 IMP 上证明了具有不同组成和/或更高厚度的氧化物-氢氧化物层的形成。LiO 从氧化物层溶解，但金属锂仍存在于基体中。