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Is stainless steel really stainless in construction application? Stainless steel refers to alloy steels with more than 10.5% of chromium and consists of  several groups like austenitic, ferritic, martensitic etc. Austenitic stainless steel is normally  used in structural applications because of its high corrosion resistance. Austenitic and  ferritic types of stainless steel cover about 95% of stainless steel applications. Stainless  steel is not stainless although it is corrosion resistant under a wide range of conditions. A passive layer of chromium oxide is formed on stainless steel’s surface which renders it  corrosion resistant. This chromium oxide layer acts as a stiff physical barrier to guard  against corrosion and makes it chemically stable. Moreover, when this layer is damaged, it  can perform self repairing where there is a sufficient supply of oxygen. However, stainless  steel will still corrode by pitting in marine environment wher...

Which type of bar reinforcement is more corrosion resistant, epoxy-coated bars,  stainless steel bars or galvanized bars? Based on the experiment conducted by the Building Research Establishment, it was shown  that the corrosion resistance of galvanized steel was the worst among the three types of bar  reinforcement. For galvanized steel bars, corrosion started to occur when a certain chloride  content in concrete (i.e. 0.4% by cement weight) was exceeded. However, for epoxy-coated  bars, they extended the time taken for cracking to occur when compared with galvanized  steel bars. The best corrosion resistant reinforcement among all is stainless steel. In particular,  austenitic stainless steel stayed uncorroded even there was chloride contamination in  concrete in the experiment. Reference is made to K. W. J. Treadaway (1988).