Evaluation of Bearing Steel Corrosion in Oil Contaminated with Synthetic Seawater

Lubricant systems in military aircrafts, operating in marine environments, experience corrosion due to seawater contamination.In particular, low chromium martensitic bearing and gear steels are susceptible to pitting corrosion attack in seawater-contaminated lubricants.Therefore, the corrosion performance of two advance bearing steels was assessed in this study.The steels were immersed in oil solutions and the corrosion results were analyzed as a function of seawater content and time.Optical image analysis was used to measure the pit density/size/distribution and an optical profiler was used to measure pit depth.It was found that while the pit surface fraction (pit surface area/total area) and pit depth increased with seawater content and time, the actual chloride content in the oil might have made a greater contribution to the corrosion damage.