Abstract: Measurement of a mechanical characteristic of a long metallic product. The long product is passed through at least one turn of an electromagnetic coil energized with a variable current, the impedance of the electromagnetic coil is measured continuously and the mechanical characteristic of the long product or variations therein are determined by comparing the measured impedance with at least one predetermined impedance value. The method can be used in particular to regulate the production of hyperquenched austenitic steel spring wire containing martensite (.alpha.') by drawing the wire through successive dies. The impedance of the coil through which the wire passes when it leaves the die is measured in order to regulate at least one of the following parameters: the temperature of the die and the wire and the wire speed.
Type:
Grant
Filed:
March 2, 1999
Date of Patent:
December 26, 2000
Assignee:
Sprint Metal-Societe de Production Internationale de Trefiles
Abstract: Stainless steel wire of diameter smaller than 2 mm and with a tensile strength greater than 2100 MPa, consisting of a steel whose chemical composition includes, by weight: 0%.ltoreq.C.ltoreq.0.03%, 0%.ltoreq.Mn.ltoreq.2%, 0%.ltoreq.Si.ltoreq.0.5%, 8%.ltoreq.Ni.ltoreq.9%, 17%.ltoreq.Cr.ltoreq.18%, 0%.ltoreq.Mo.ltoreq.0.4%, 3%.ltoreq.Cu.ltoreq.3.5%, 0%.ltoreq.N.ltoreq.0.03%, S.ltoreq.0.01%, P.ltoreq.0.04%, the remainder being iron and impurities resulting from the production. Process of manufacture of the wire and uses.
Type:
Grant
Filed:
December 18, 1997
Date of Patent:
August 22, 2000
Assignees:
Sprint Metal Societe de Production Internationale de Trefiles, Imphy S.A., Ugine Savoie
Abstract: Steel, steel wire, and a process for forming a drawn wire, especially tire-reinforcing wire of diameter smaller than 0.4 mm, by drawing a steel of the following composition by weight: 0.005%.ltoreq.carbon.ltoreq.0.050%; 0.005%.ltoreq.nitrogen.ltoreq.0.050%; 0.1%.ltoreq.silicon.ltoreq.2.0%; 0.1%.ltoreq.manganese.ltoreq.5%; 5%.ltoreq.nickel.ltoreq.12%; 10%.ltoreq.chromium.ltoreq.20%; 0.01%.ltoreq.copper.ltoreq.4%; 0.01%.ltoreq.molybdenum.ltoreq.3%,the base wire being subjected to:drawing to a cumulative deformation ratio .epsilon. of larger than 2 and smaller than 4,an intermediate annealing treatment at above 700.degree. C.final drawing to a cumulative deformation ratio .epsilon. of smaller than 4.5 and larger than 3.
Type:
Grant
Filed:
April 29, 1999
Date of Patent:
April 11, 2000
Assignees:
Ugine-Savoie Imphy, Sprint Metal - Societe de Production Internationale de Trefiles