Surface treatment process for steels and article
AssigneeAgence Nationale de Valorisation de la Recherche (ANVAR)
InventorsJacques Galland, Dominique Boutard nee Gabillet, Jacques Chene
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Abstract
A process for treating a steel surface, comprising the steps of immersing the surface in a bath of molten tin at a temperature and for a period of time suitable to cause a layer of tin containing diffused iron to adhere to the surface and, after removal of the surface from the bath, removing a surface layer in which iron and tin accord substantially with the formula of Fe Sn.sub.2 so as to expose a layer in which iron and tin accord substantially to the formula Fe Sn.
Claims34
A method of providing a hard and corrosion resistant layer comprising iron and tin on a surface of a steel substrate which comprises:
- immersing a surface of a steel substrate in a bath of molten tin maintained at a temperature of from 400.degree. to 700.degree. C for a period of time sufficient to cause a tin-containing layer containing diffused iron to adhere to said surface, said tin-containing layer comprising a first, inner, portion adjacent the steel substrate containing iron and tin in amounts corresponding substantially to the formula FeSn, a second portion adjacent said first portion containing iron and steel in amounts corresponding substantially to the formula FeSn.sub.2, and a third, outer, portion of tin adjacent said second portion;
- removing said surface bearing said tin-containing layer from said bath;
- and removing said third portion and said second portion of said tin-containing layer to provide said surface of said steel substrate with a hard and corrosion resistant layer containing iron and tin in amounts corresponding substantially to the formula FeSn.
A steel substrate having a surface bearing a hard and corrosion resistant layer having a thickness of about 50 to 100 microns, and containing iron and tin in amounts corresponding substantially to the formula FeSn.
Dependencies are inferred from the claim text.