Born in Ramsden's Yard near the Wicker on 18th February 1871. His father, John was employed at Firth's crucible steel furnaces. Harry started work at the age of twelve as a cellar lad at the same crucible steel workshop as his father. Shortly afterwards, he was moved to the firm's laboratories, where he worked as general assistant. By the age of twenty, he was apprenticed as a laboratory assistant.
In 1912, he was investigating corrosion (rusting) of rifle barrels. As a result of his investigations, he developed a chrome alloy steel which was much more rust resistant than the steel which had been
used until then. Brearley resigned from the Firth company in 1915 after arguments about the ownership of the rights to the invention of stainless steel. The company claimed that they owned the rights as Brearley was an employee of the firm. Brearley claimed that he should be entitled to at least half of the ownership.
Harry became works manager at Brown Bayley's Steel Works in Sheffield, where he continued with the development and production of stainless steel. He was awarded the Iron and Steel Institute's Bessemer Gold Medal in 1920. He eventually became a director of Brown Bayley in 1925.
Brearley's chrome steel formed the basis for the wide range of stainless and special steels which are now used so widely .
Harry Brearley died in 1948, in Torquay.