Corrosion fatigue behavior of Al-5Mg coated AISI 316L stainless steel in sodium chloride environments under bending load

Abstract

PurposeThe purpose of this study is to describe the environmentally assisted cracking (EAC) of AISI 316L stainless steel as bare and coated cases in several corrosion environments. The main purpose of this study is to extend the lifespan of 316L material under corrosive fatigue in sodium chloride environments.Design/methodology/approachFatigue tests carried out by using a Schenk type plane bending fatigue machine made by Tokyokoki Co. A scanning electron microscope (SEM) was used to observe the fracture surfaces and tested specimen surfaces. The micro-Vickers hardness of specimens was measured by using a PC-controlled Buehler–Omnimet tester.FindingsUnder reciprocating bending condition (R = −1) the behavior of 316L SS bare samples and 316L SS coated with Al-5%Mg samples were investigated comparatively at room temperature in ambient air and in several corrosion solutions. The results obtained from the data showed that Al-5Mg coating procedure significantly stabilized the 316L SS even in the most aggressive environment 5 per cent NaCl solution as compared with bare samples.Originality/valueAl-5Mg coating showed a stable structure under the corrosion liquids used in the experiments. The coating material served as a stable barrier between the base material and the corrosion fluid, thus ensuring a tightness even in long-term tests below the endurance limit.