Stainless Steel & Manufacturing

Stainless Steel or Inox steel from the French "inoxyable" was first discovered in 1913. An English metallurgist, Harry Brearly accidentally discovered Stainless Steel while working on a project to improve rifle barrels. He discovered that by adding chromium to low carbon steel, it gave the metal a stain resistant quality.

Stainless steel is defined as an alloy contacting a minimum of 10.5% to 12% of chromium content by mass. Modern Stainless steel also contains varying amounts of nickel, molybdenum, titanium, niobium and carbon depending on the application of the alloy.

Stainless Steel does not corrode or rust as easily as ordinary carbon steel, but it is not stain poof. It is know as corrosion resistant steel. Unprotected carbon steel rusts (iron oxide) readily when exposed to air and moisture. The Stainless Steel's chromium content is sufficient to form a passive film of chromium oxide which prevents further surface corrosion. This layer is only a few atoms thick and invisible to the naked eye. If the metal is cut or scratched and the passive film is disrupted, more oxide will quickly form and recover the exposed surface, protecting it from corrosion.

There are different grades and surface finishes of stainless steel to suit the environment the alloy must endure. Cape Stainless predominantly works with 3 main types of brushed stainless steels, Grade 430, Grade 304 and Grade 316. The most commonly used of these is grade 304. The most cost efficient of these is Grade 430, but it is also the least corrosion resistant and the most brittle. Grade 316 is the most corrosion resistant, but also the most costly and seldom used except in specific applications.

Cape Stainless sources Grade 304 & 430 material in coils rather than the more commonly supplied sheets. This allows for the fabrication of units longer than the normal maximum of 2250mm. The coils are cut to the required length and then shaped, bent and welded as required.