EASTEEL
Stainless steel is manufactured in a variety of different alloys. The percent of Chrome and other metals determine which alloy of stainless is produced. Not all versions of stainless is rust proof, just rust resistant.
There are also version of steel, Monel and Inconel, that most would consider ‘stainless’. Salt water will rapidly affect most versions of stainless with what is called “cloride stress corrosion” which cause a failure of the lattice structure of the metal.
Generally, some stainless steel with a lower chrome content may appear to have discoloration that appears to be rust.
Steel is a iron alloy with composites like carbon and with a minimum chromium percentage of 10.5 …and the strength and other properties are closely related to the percentage of carbon and chromium used in it..! its the chromium that creates a thin oxide layer maintaining the lustre by preventing the alloy from forming the iron oxide which is often reffered as rust..so if you got your stainless steel rusted you are betryed by the manufactures and may be they have failed to anticipate the sorrounding environment so that they selected a compostion that best suits.