Stainless steel has demonstrated a reduced tendency to gall. The corrosion resistance of iron-chromium alloys was first recognized in 1821 by French metallurgist Pierre Berthier, who noted their resistance against attack by some acids and suggested their use in cutlery. Metallurgists of the 19th century were unable to produce the combination of low carbon and high chromium found in most modern stainless steels, and the high-chromium alloys they could produce were too brittle to be practical. In 1872, the Englishmen John T. Woods and John Clark patented a "Water Resistant" alloy in Britain, that would today be considered a stainless steel. In
Stainless steel are relatively poor conductors of electricity, with significantly lower electrical conductivity than copper. Ferritic and martensitic stainless steels are magnetic. Annealed austenitic stainless steels are non-magnetic. Work hardening can make austenitic stainless steels slightly magnetic. Galling, sometimes called cold welding, is a form of severe adhesive wear which can occur when two metal surfaces are in relative motion to each other and under heavy pressure. Austenitic stainless steel fasteners are particularly susceptible to thread galling, although it also occurs in other alloys that self-generate a protective oxide surface film, such as aluminum and titanium. Under high contact-force sliding this oxide