Many boxes sold,
Harry Brearley (February 18, 1871 – August 12, 1948) was the inventor of
"rustless steel" (later to be called "stainless steel"). He was born in
Brearley had humble beginnings as the son of a steel melter. He left school
at the age of twelve to enter his first employment as a labourer in one of the
city's steelworks, being transferred soon afterwards to the post of general
assistant in the company's chemical laboratory.
For several years, in addition to his laboratory work, he studied at home and
later in formal evening classes, to specialize in steel production techniques
and associated chemical analysis methods.
By his early thirties, Brearley had earned a reputation as an experienced
professional and for being very astute in the resolution of practical,
industrial, metallurgical problems. It was in 1908, when two of Sheffield's
steelmaking companies innovatively agreed to jointly finance a common
research laboratory (Brown Firth Laboratories) that Harry Brearley was asked to
lead the project.
Brearley died in 1948, at
coastal resort in the south of England.
Development of stainless steel
In the troubled years immediately before World War I, arms manufacturing
increased significantly in England, but practical problems were encountered due
to erosion (excessive wear) of the internal surfaces of gun barrels. Brearley
began to research new steels which could better resist the erosion caused by
high temperatures (rather than corrosion, as is often mentioned in this regard).
He began to examine the addition of chromium to steel, which was known to raise
the material’s melting point, as compared to the standard carbon steels.
The research concentrated on quantifying the effects of varying the levels of
carbon (C, at concentrations around 0.2 weight %) and chromium (Cr, in the range
of 6 to 15 weight %).
In order to undertake
metallography to study the microstructure of the experimental alloys (the
main factor responsible for a steel's mechanical properties) it was necessary to
polish and etch the metallic samples produced. For a carbon steel, a dilute
solution of nitric acid in alcohol is sufficient to produce the required
etching, but Brearley found that the new chromium steels were very resistant to
It was probably Harry Brearley’s upbringing in Sheffield, a city famous for
the manufacture of cutlery since the 16th century, which led him to appreciate
the potential of these new steels for applications not only in high temperature
service, as originally envisioned, but also in the mass production of
food-related applications such as cutlery, saucepans and processing equipment
etc. With this in mind he extended his examinations to include tests with food
acids such as vinegar and lemon juice, with very promising results. (Up to that
time carbon steel knives were prone to unhygienic rusting if they were not
frequently polished and only expensive sterling silver or
cutlery was generally available to avoid such problems). Brearley initially
called the new alloy "rustless steel"; the more euphonic "stainless steel" was
suggested by Ernest Stuart of R.F. Moseley's, a local cutlery manufacturer, and
eventually prevailed. It is reported that the first true stainless steel,
a 0.24wt% C, 12.8wt% Cr ferrous alloy, was produced by Brearley in an electric
furnace on August 13, 1913. He was subsequently awarded the Iron and Steel
Institute's Bessemer Gold Medal in 1920.
Virtually all research projects into the further development of stainless
steels were interrupted by the 1914-18 War, but efforts were renewed in the
1920s. Though Harry Brearley had left the Brown Firth Laboratories in 1915,
following disagreements regarding patent rights, the research did continue there
under the direction of his successor, Dr. W. H. Hatfield.
It is Hatfield who is credited with the development, in 1924, of a stainless
steel which even today is probably the widest-used alloy of this type, the
so-called "18/8", which in addition to chromium, includes nickel (Ni) in its
composition (18wt% Cr, 8wt% Ni).