通过在半乡村、工业酸雨和海洋大气环境中为期20年的现场暴露试验,研究了带包铝层的LCA的腐蚀失重规律和机械性能损失情况,并利用金相显微镜、扫描电镜(SEM)、能谱仪(EDS)和红外光谱仪(FTIR)分析了表面和截面的腐蚀形貌以及腐蚀产物组成。结果表明,LC4的腐蚀失重在工业污染和海洋大气环境中较大,在半乡村大气环境中很小,腐蚀失重随暴露时间的关系接近线性变化。带包铝层的LC4在3种大气环境中暴露20年后仍保持着优异的机械性能,且点蚀都未穿透LC4的包铝层。LC4在工业污染和海洋大气环境中的腐蚀产物都为水合氢氧化铝。
Atmospheric corrosion behaviors of alclad LC4 were investigated in rural, marine and industrial atmospheres in China for over 20 years. Corrosion weight loss and loss in mechanical properties were measured. Appearance, cross-section photomicrograph and corrosion products were observed and analyzed by SEM, EDS and FTIR. The results demonstrated that the weight loss was higher in industrial and marine atmospheres and lower in rural atmosphere. The relation of weight losses versus exposure time was linear ap- proximately. Alclad LC4 still performed excellent me- chanical properties after 20 years exposed in the three kinds of atmosphere, and the pitting did not penetrate the cladding of LC4. The corrosion products were all composed of hydrated aluminum hydroxide in industri- al and marine atmospheres.