Harry Brearley
Harry Brearley (18 February 1871 – 14 July 1948) was an English metallurgist, usually credited with the invention of "rustless steel" (later to be called "stainless steel" in the anglophone world).
Stainless steel
There are over 150 grades of stainless steel, of which 15 are most commonly used. There are a number of systems for grading stainless and other steels, including US SAE steel grades.