Edge Formability In Metallic Alloys

摘要

This disclosure is directed at methods for mechanical property improvement in a metallic alloy that has undergone one or more mechanical property losses as a consequence of shearing, such as in the formation of a sheared edge portion or a punched hole. Methods are disclosed that provide the ability to improve mechanical properties of metallic alloys that have been formed with one or more sheared edges which may otherwise serve as a limiting factor for industrial applications.

主权项

1. A method for improving one or more mechanical properties in a metallic alloy that has undergone a mechanical property loss as a consequence of the formation of one or more sheared edges comprising:
a. supplying a metal alloy comprising at least 50 atomic % iron and at least four or more elements selected from Si, Mn, B, Cr, Ni, Cu or C and melting said alloy and cooling at a rate of ≦250 K/s or solidifying to a thickness of ≧2.0 mm up to 500 mm and forming an alloy having a Tm and matrix grains of 2 μm to 10,000 μm; b. heating said alloy to a temperature of 700° C. and below the Tm of said alloy and at a strain rate of 10−6 to 104 and reducing said thickness of said alloy and providing a first resulting alloy having a tensile strength of 921 MPa to 1413 MPa and an elongation of 12.0% to 77.7%; c. stressing said first resulting alloy and providing a second resulting alloy having a tensile strength of 1356 MPa to 1831 MPa and an elongation of 1.6% to 32.8%; d. heating said second resulting alloy to a temperature of below Tm and forming a third resulting alloy having matrix grains of 0.5 μm to 50 μm and having an elongation (E1); e. shearing said alloy and forming one or more sheared edges wherein said alloy's elongation is reduced to a value of E2 wherein E2=(0.57 to 0.05) (E1); f. reheating said alloy with said one or more sheared edges wherein said alloy's reduced elongation observed in step (d) is restored to a level having an elongation E3=(0.48 to 1.21)(E1).