(中國科學(xué)院金屬研究所 材料環(huán)境腐蝕研究中心，沈陽 110016)
摘 要: 通過在我國西北格爾木典型大氣環(huán)境進行大氣暴露實驗，測定LC4鋁合金在該地區(qū)的腐蝕率；利用掃描電鏡(SEM)、能量色散X射線譜(EDX)、電子探針(EPMA)、 紅外光譜(FTIR)和X射線衍射儀(XRD)觀察分析LC4鋁合金腐蝕表面形貌、元素分布和腐蝕產(chǎn)物結(jié)構(gòu)。結(jié)果表明：LC4鋁合金的腐蝕以點蝕為主要特征，比其在非鹽湖大氣環(huán)境中的腐蝕嚴重，朝地面的腐蝕比朝天面嚴重，腐蝕產(chǎn)物層中含有大量的氧和鋁，較多的氯和硫；主要腐蝕產(chǎn)物為Al2O3，Al2O3∙2SiO2∙2H2O和Al2Cl6∙6H2O；含氯和硫的鹽參與鋁合金的大氣腐蝕過程，并起到促進腐蝕的作用。
關(guān)鍵字: 鋁合金；大氣腐蝕；鹽湖；表面分析
salt lake atmosphere
（Environmental Corrosion Centre, Institute of Metal Research, Chinese Academy of Sciences,
Shenyang 110016, China）
Abstract:The corrosion behaviors of typical high-strength aluminum alloy LC4 was studied by atmospheric exposure test, combining the experimental techniques including mass loss, morphological check of samples and analysis of corrosion products. The products formed on aluminum alloy LC4 exposed for 12 months were characterized by X-ray diffractometry(XRD) and infrared transmission spectroscopy (IRS), the results show that the main products are Al2O3, Al2O3∙2SiO2∙2H2O and Al2Cl6∙6H2O. The surface morphology was observed by scanning electron microscopy (SEM). The morphology of cross section of skyward surface exposed in salt lake atmosphere for 6 months and the distributions of O, Cl, S, Si and Al were analyzed by electron probe micro analyzer (EPMA). Corrosion on field-ward surface is more severe than that on skyward surface. The character of the corrosion products is related to the abundant chloride environment.
Key words: aluminum alloy; atmospheric corrosion; salt lake; surface analysis
