Strength and Ductility with Boron Quench Tempering Steels 680128
The use of boron to increase the hardenability of steel (including low carbon steel) is an old concept widely used during the war years. Also it has been generally known that boron does not materially affect the hot or cold working properties of the steel. However, no one capitalized on these features to produce ductile high strength fasteners until U. S. Steel recently introduced a family of low carbon boron quench tempering steels.
High strength fasteners and special parts produced from these steels offer such a fine combination of strength and ductility that they are, in most ways, superior to the highest strength fasteners and parts made from commonly used medium carbon alloy steels.
In addition, the use of these steels will result in substantial manufacturing economies and broaden the possibilities for difficult cold forming of high strength heat treated parts.