Drawing process and wire obtained by drawing process
AssigneeCompagnie Generale Des Etablissements Michelin
InventorsArnaud Verleene, Laurent Bucher, Olivier Giroux
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Abstract
A steel wire has a microstructure that is completely ferritic, a mixture of ferrite and cementite or a mixture of ferrite and pearlite and has a weight content of carbon C such that C<0.05% and a weight content of chromium Cr such that Cr<12%. The process for drawing the wire comprises: at least one first uninterrupted series of steps of drawing the wire from a diameter D to a diameter d′, at least one second uninterrupted series of steps of drawing the wire of diameter d′ to a diameter d, and one or more intermediate steps between the first and second uninterrupted series of steps of drawing the wire, the wire having a temperature less than or equal to 300° C. during the or each intermediate step.
Claims31
A process for drawing a steel wire, the steel wire having a microstructure that is selected from the group consisting of completely ferritic, a mixture of ferrite and cementite, and a mixture of ferrite and pearlite, and the wire having a weight content of carbon C such that C<0.05% and a weight content of chromium Cr such that Cr<12%, the process comprising:
- at least one first uninterrupted series of steps of drawing the wire from a diameter D to a diameter d′;
- at least one second uninterrupted series of steps of drawing the wire of diameter d′ to a diameter d;
- wherein, with D and d being expressed in mm, the true strain εT=2 ln (D/d) is such that εT≥6;
- and
- one or more intermediate steps between the first and second uninterrupted series of steps of drawing the wire, the wire having a temperature less than or equal to 300° C. during the one or more intermediate steps,
- wherein the one or more intermediate steps do not comprise a heat treatment step during which the steel of the steel wire is heated beyond an austenitizing temperature of the steel.
A process for drawing a steel wire, the steel wire having a microstructure that is selected from the group consisting of completely ferritic, a mixture of ferrite and cementite, and a mixture of ferrite and pearlite, and the wire having a weight content of carbon C such that C<0.05% and a weight content of chromium Cr such that Cr<5%, the process comprising:
- at least one first uninterrupted series of steps of drawing the wire from a diameter D to a diameter d′;
- at least one second uninterrupted series of steps of drawing the wire of diameter d′ to a diameter d;
- wherein, with D and d being expressed in mm, the true strain εT=2 ln (D/d) is such that εT≥6;
- and
- one or more intermediate steps between the first and second uninterrupted series of steps of drawing the wire, the wire having a temperature less than or equal to 300° C. during the one or more intermediate steps,
- wherein the one or more intermediate steps do not comprise a heat treatment step during which the steel of the steel wire is heated beyond an austenitizing temperature of the steel.
Dependencies are inferred from the claim text.