William Herbert Hatfield (10 April 1882 – 16 October 1943) was an English metallurgist who contributed to the development of stainless steel.
[1] Hatfield was appointed Director of the Brown - Firth Research Laboratories in Sheffield in 1916 (succeeding Harry Brearley and continuing Brearley's work on stainless steel), and later joined the Board of Messrs Thomas Firth and John Brown Limited.
[2] In 1940 he devised "Rex 78", a stainless steel alloy for use in Frank Whittle's turbojet engine project, the material being first used in the Power Jets W.1.
[3] He authored a variety of technical papers on metallurgy, with particular reference to rust, acid and heat-resistant steels and cast iron.
[4] There is an Annual memorial lecture held in December each year at Sheffield University, called the "Hatfield Memorial Lecture" funded by a Trust set up in 1944.