EP 2488671 A1 20120822 - HEAT TREATMENT OF MARTENSITIC STAINLESS STEEL AFTER REMELTING UNDER A LAYER OF SLAG
Title (en)
HEAT TREATMENT OF MARTENSITIC STAINLESS STEEL AFTER REMELTING UNDER A LAYER OF SLAG
Title (de)
WÄRMEBEHANDLUNG VON MARTENSITISCHEM EDELSTAHL NACH DEM UMSCHMELZEN UNTER EINER SCHLACKESCHICHT
Title (fr)
TRAITEMENTS THERMIQUES D'ACIERS MARTENSITIQUES INOXYDABLES APRES REFUSION SOUS LAITIER
Publication
Application
Priority
- FR 0957110 A 20091012
- FR 2010052142 W 20101011
Abstract (en)
[origin: WO2011045515A1] The invention relates to a method for producing a martensitic stainless steel that includes a step in which an ingot of the steel is remelted under a layer of slag, a subsequent step in which the ingot is cooled and at least one austenitic thermal cycle consisting in heating the ingot above the austenitic temperature thereof, followed by a cooling step. During each of the cooling steps, if the cooling step is not followed by an austenitic thermal cycle, the ingot is maintained at a holding temperature within the ferrite-pearlite transformation nose region for a holding time greater than that required to transform the austenite as completely as possible into a ferrite-pearlite structure in the ingot at the holding temperature, whereby the ingot is maintained at the holding temperature once the temperature of the coolest point in the ingot has reached said holding temperature. Moreover, during each of the cooling steps, if the cooling step is followed by an austenitic thermal cycle, before the minimum temperature of the ingot drops below the martensitic transformation start temperature Ms, the ingot is either: maintained at a temperature above the heating-induced austenitic transformation finish temperature Ac3 for the entire duration between these two austenitic thermal cycles, or maintained at the holding temperature within the ferrite-pearlite transformation nose region, as above.
IPC 8 full level
C21D 3/06 (2006.01); B21B 45/02 (2006.01); C21D 9/00 (2006.01); C21D 9/70 (2006.01); C22B 9/18 (2006.01)
CPC (source: EP US)
C21D 3/06 (2013.01 - EP US); C21D 9/0081 (2013.01 - EP US); C21D 9/70 (2013.01 - EP US); C22B 9/18 (2013.01 - EP US); C21D 2211/001 (2013.01 - EP US); C21D 2211/005 (2013.01 - EP US); C21D 2211/008 (2013.01 - EP US); C21D 2211/009 (2013.01 - EP US)
Citation (search report)
See references of WO 2011045515A1
Designated contracting state (EPC)
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
DOCDB simple family (publication)
FR 2951198 A1 20110415; FR 2951198 B1 20130510; BR 112012008524 A2 20160405; BR 112012008524 B1 20180417; CA 2776851 A1 20110421; CA 2776851 C 20180130; CN 102575311 A 20120711; CN 102575311 B 20141210; EP 2488671 A1 20120822; EP 2488671 B1 20201125; JP 2013507532 A 20130304; JP 5778158 B2 20150916; RU 2012119551 A 20131120; RU 2567409 C2 20151110; US 2012199252 A1 20120809; US 8808474 B2 20140819; WO 2011045515 A1 20110421
DOCDB simple family (application)
FR 0957110 A 20091012; BR 112012008524 A 20101011; CA 2776851 A 20101011; CN 201080046203 A 20101011; EP 10781971 A 20101011; FR 2010052142 W 20101011; JP 2012533673 A 20101011; RU 2012119551 A 20101011; US 201013501610 A 20101011