Global Patent Index - EP 0953651 B1

EP 0953651 B1 20030625 - Stainless steel for manufacturing drawn wire, especially tyre reinforcement wire, and wire manufactured by said process

Title (en)

Stainless steel for manufacturing drawn wire, especially tyre reinforcement wire, and wire manufactured by said process

Title (de)

Rostfreier Stahl zur Herstellung von gezogenem Draht, insbesondere zur Verstärkung von Reifen, und so hergestellter Draht

Title (fr)

Acier inoxydable pour l'élaboration de fil tréfilé en acier inoxydable, notamment de fil de renfort de pneumatique et fil obtenu par le procédé

Publication

EP 0953651 B1 20030625 (FR)

Application

EP 99400979 A 19990422

Priority

FR 9805356 A 19980429

Abstract (en)

[origin: EP0953651A1] A drawn steel wire is produced by drawing an austenitic stainless steel of specified composition to produce a high tensile fracture stress without excessive martensite formation. A drawn steel wire is produced from a greater than 5 mm diameter wire-rod or a pre-drawn wire of a steel of composition (in wt.%) 0.005-0.050 C, 0.005-0.050 N, 0.1-2 Si, 0.1-5 Mn, 5-12 Ni, 10-20 Cr, 0.01-4 Cu, 0.01-3 Mo, 0.0001-0.030 S, 0.005-0.10 P, less than 0.5 each (less than 1 total) impurities and balance Fe, the sum of C% + N% being ≤ 60 x 10<-3> and the JM value being -55 to -30 exclusive, where JM = 551 - 462 x (C% + N%) - 9.2 x Si% - 20 x Mn% - 13.7 x Cr% - 29 x (Ni% + Cu%) - 18.5 x Mo%. The process comprises (a) initial drawing with a cumulative reduction epsilon of 2-4 exclusive at below 600 degrees C without intermediate anneals to obtain a 0.7-2 mm diameter wire; (b) intermediate annealing at above 700 degrees C; (c) optional conditioning; and (d) final drawing with a cumulative reduction epsilon of 3-4.5 exclusive at below 600 degrees C without intermediate anneals to obtain a 0.1-0.4 mm diameter wire. An Independent claim is also included for a steel wire obtained by the above process, the wire optionally being coated with copper, brass or zinc and diffusion treated prior to the final drawing stage.

IPC 1-7

C21D 8/06; C22C 38/42

IPC 8 full level

C21D 8/06 (2006.01); C21D 9/52 (2006.01); C22C 38/02 (2006.01); C22C 38/40 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/58 (2006.01)

CPC (source: EP US)

C21D 8/065 (2013.01 - EP US); C21D 9/525 (2013.01 - EP US); C22C 38/02 (2013.01 - EP US); C22C 38/40 (2013.01 - EP US); C22C 38/42 (2013.01 - EP US); C22C 38/44 (2013.01 - EP US); C22C 38/58 (2013.01 - EP US); Y10T 428/12778 (2015.01 - EP US); Y10T 428/12924 (2015.01 - EP US)

Designated contracting state (EPC)

AT BE CH DE DK ES FI FR GB GR IE IT LI LU NL PT SE

DOCDB simple family (publication)

EP 0953651 A1 19991103; EP 0953651 B1 20030625; AT E243770 T1 20030715; DE 69909012 D1 20030731; DE 69909012 T2 20040401; FR 2778188 A1 19991105; FR 2778188 B1 20000602; US 6048416 A 20000411

DOCDB simple family (application)

EP 99400979 A 19990422; AT 99400979 T 19990422; DE 69909012 T 19990422; FR 9805356 A 19980429; US 30157299 A 19990429