EP 1795617 A1 20070613 - Process for heat treating an electrical steel sheet
Title (en)
Process for heat treating an electrical steel sheet
Title (de)
Verfahren zum Wärmebehandeln eines Elektroblech-Stahlbands
Title (fr)
Procédé de traitement thermique pour une tôle magnétique
Publication
Application
Priority
DE 102005059308 A 20051209
Abstract (en)
Heat treatment method for steel strip comprises continuous annealing followed by cooling in three stages. In the first stage the strip is cooled to a temperature 50[deg]C above the Curie temperature. In the second stage it is cooled to 80[deg]C below the Curie temperature and in the final stage with a cooling gradient up to 85[deg]C/s. Heat treatment method is used for steel strip with an Si and Al content (wt%) given by the relationship: 0.9=Si + 2 x Al =1.8, an Mn content up to 2.5 wt%, up to 1 wt% of each of P, Cr and Ni and up to 0.1 wt% of each of C, N and S. The method comprises continuous annealing followed by cooling in three stages. In the first stage the strip is cooled to a temperature 50[deg]C above the Curie temperature with a cooling gradient of -38[deg] to -1[deg]C/s. In the second stage it is cooled to 80[deg]C below the Curie temperature. The cooling gradient has an upper limit (CR 2 M A X) given by: CR 2 M A X = pi (cos(2(T B A N D - T C)pi /2 6>((T B A N D - T C)(pi /2 6>) 2> + 1)) - 1) - pi . Its lower limit (CR 2 M I N) is given by: (CR 2 M I N) = 3pi (cos(2(T B A N D - T C)pi /2 6>((T B A N D - T C)(pi /2 6>) 2> + 1)) - 1) - pi . In the final stage the cooling gradient is up to 85[deg]C/s.
IPC 8 full level
C21D 6/00 (2006.01); C21D 8/02 (2006.01); C21D 8/12 (2006.01); C21D 9/52 (2006.01); C21D 9/46 (2006.01)
CPC (source: EP)
C21D 6/00 (2013.01); C21D 8/0273 (2013.01); C21D 9/46 (2013.01)
Citation (applicant)
- EP 0357797 A1 19900314 - NIPPON KOKAN KK [JP]
- JP S5296919 A 19770815 - KAWASAKI STEEL CO
Citation (search report)
- [X] JP S5296919 A 19770815 - KAWASAKI STEEL CO
- [DA] EP 0357797 A1 19900314 - NIPPON KOKAN KK [JP]
- [A] EP 0538519 A1 19930428 - ARMCO INC [US]
- [A] JP H04221019 A 19920811 - SUMITOMO METAL IND
- [A] US 3130088 A 19640421 - COOK LOWELL L
- [A] DE 1583349 A1 19730816 - CREUSOT LOIRE
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA HR MK YU
DOCDB simple family (publication)
EP 1795617 A1 20070613; EP 1795617 B1 20140226; EP 1795617 B9 20141029; DE 102005059308 A1 20070614; ES 2464865 T3 20140604; PL 1795617 T3 20140829; SI 1795617 T1 20140630
DOCDB simple family (application)
EP 06125750 A 20061208; DE 102005059308 A 20051209; ES 06125750 T 20061208; PL 06125750 T 20061208; SI 200631780 T 20061208