ABSTRACT

The mild carbon steel (CS) A-36 and weathering steel A-588 were exposed to the outdoor atmosphere at two different locations in tropical Panama. After a 10-year exposure, the results indicate that the chloride deposition rate and the type of steel play an important role in the corrosion behaviour of tested steels. Both types of steel mainly contain lepidocrocite and goethite as corrosion products at the urban site, while the corrosion products of steels exposed to a moderate marine atmosphere consisted of lepidocrocite, goethite and maghemite. The large fractions of maghemite in the corrosion products of steel A-36 suggest that this phase is interrelated to the higher corrosion rate of CS in the moderate atmospheric environment.

摘要

低碳钢 (CS) A-36 和耐候钢 A-588 在热带巴拿马的两个不同位置暴露在室外大气中。经过 10 年的暴露，结果表明氯化物沉积速率和钢的类型在受试钢的腐蚀行为中起着重要作用。这两种钢材在城市现场主要含有纤铁矿和针铁矿作为腐蚀产物，而暴露于中等海洋大气的钢材的腐蚀产物由纤铁矿、针铁矿和磁赤铁矿组成。钢 A-36 腐蚀产物中大量的磁赤铁矿表明该阶段与中等大气环境中 CS 的较高腐蚀速率相关。