舱外设备箱体模拟海洋大气环境中的加速腐蚀试验与结果分析

Accelerated Corrosion Test and Result Analysis of Extracurricular Equipment Box in Simulated Marine Atmospheric Environment

目的 研究模拟海洋大气环境对舱外设备箱体腐蚀行为的影响,为快速评价舱外设备箱体原材料、原结构、原表面技术状态改进优劣提供技术和方法支撑。方法 根据XX舱外设备箱体实际服役环境剖面、腐蚀损伤状况,制定含海水模拟、湿热、维护保养及检查阶段等3个模块的实验室模拟海洋大气环境加速谱,运用外观、扫描电镜(SEM)、金相显微镜、X射线能谱(EDS)等表征技术,研究设备箱体在12个循环周期的宏微观形貌和腐蚀产物元素含量分布,并对标准金属铝和钢的同步实验室试验与XX近海户外自然环境下的腐蚀效应进行对比。结果 12个循环周期结束后,底座铝合金严重腐蚀,呈现明显的晶间腐蚀,并产生大量腐蚀产物,腐蚀产物主要含有O、Na、Al、Si、Cl、Ca、Mn、Fe等元素,其腐蚀形貌及程度与实际服役5 a的底座一致。标准金属铝和钢加速试验120 d的腐蚀效应分别等效XX近海大气试验4.65 a和10.57 a。结论 海水模拟、湿热、维护保养及检查阶段等3个模块的实验室模拟循环试验能较好地模拟XX舱外设备箱体经历的环境,其腐蚀与实际服役环境下的腐蚀程度相近,实现了基于短期内完成3~5 a的海洋运行验证。

The work aims to investigate the impact of simulated marine atmospheric environment on the corrosion behavior of extravehicular equipment cabin,in order to provide technical and methodological support for quickly evaluating the improvement of raw materials,structures,and surface technical conditions of extravehicular equipment cabin.Based on the actual service environment profile and corrosion damage status of the equipment box outside the XX cabin,a laboratory simulated marine atmospheric environment acceleration spectrum was developed with three modules:seawater simulation,humid heat,maintenance and inspection stage.Characterization techniques such as appearance,scanning electron microscopy(SEM),metallographic microscopy,and X-ray energy dispersive spectroscopy(EDS) were used to study the macroscopic and microscopic morphology of the equipment box and the distribution of corrosion product element content over 12 cycle periods,and compare the corrosion effects of standard metal aluminum and steel through synchronous laboratory tests and outdoor natural environments near XX offshore.After 12 cycles,the aluminum alloy on the base was severely corroded,presenting obvious intergranular corrosion and producing a large amount of corrosion products composed of O,Na,Al,Si,Cl,Ca,Mn,and Fe elements,and their corrosion appearance and degree were similar to the base after 5 years of service.After 120 days of cyclic testing,the corrosion effects of standard metal aluminum and steel were equivalent to those of 4.65 and 10.57 years of XX offshore atmospheric test.In the laboratory simulated marine atmospheric environment cycling test of three modules,namely seawater simulation,humidity and heat,maintenance and inspection,the corrosion degree of the equipment box outside the cabin is similar to that in the actual service environment,achieving a short-term completion of 3-5years of marine operation verification.