Global Patent Index - EP 0501867 B1

EP 0501867 B1 19990107 - Method for etching steel materials such as stainless steels and alloyed steels

Title (en)

Method for etching steel materials such as stainless steels and alloyed steels

Title (de)

Verfahren zum Beizen von Stahlwerkstoffen wie z.B. rostfreien und legierten Stählen

Title (fr)

Procédé de décapage de matériaux en acier tels que les aciers inoxydables et les aciers alliés

Publication

EP 0501867 B1 19990107 (FR)

Application

EP 92400471 A 19920224

Priority

  • FR 9102222 A 19910225
  • US 15025493 A 19931110

Abstract (en)

[origin: EP0501867A1] Process for pickling-descaling a material made of steel, chosen especially from stainless steels and alloy steels, permitting the removal of an internal oxidation layer, characterised in that the material is treated with a bath containing: - an acid chosen from a halogenated acid, sulphuric acid, phosphoric acid, formic acid and acetic acid, - ferric ions in a concentration of at least 20 g/l, and the reaction conditions are adjusted so as to have conjointly a reduction of the ferric iron to ferrous iron and a reaction of dissolution of the metallic elements of the matrix of the material while maintaining the redox potential of the bath at a value of 100 to 350 mV relative to Ag/AgCl, and the acid concentration so that the quantity of hydrogen released is from 0.1 to 5 ml/cm<2> of material (measured under normal conditions).

IPC 1-7

C23G 1/08

IPC 8 full level

C23G 1/08 (2006.01)

CPC (source: EP US)

C23G 1/08 (2013.01 - EP US); C23G 1/086 (2013.01 - EP US)

Designated contracting state (EPC)

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

DOCDB simple family (publication)

EP 0501867 A1 19920902; EP 0501867 B1 19990107; AT E175452 T1 19990115; DE 69228080 D1 19990218; DE 69228080 T2 19990520; DK 0501867 T3 19990830; ES 2127208 T3 19990416; FI 920787 A0 19920224; FI 920787 A 19920826; FI 99031 B 19970613; FI 99031 C 19970925; FR 2673200 A1 19920828; FR 2673200 B1 19950303; GR 3029688 T3 19990630; US 5690748 A 19971125

DOCDB simple family (application)

EP 92400471 A 19920224; AT 92400471 T 19920224; DE 69228080 T 19920224; DK 92400471 T 19920224; ES 92400471 T 19920224; FI 920787 A 19920224; FR 9102222 A 19910225; GR 990400772 T 19990312; US 15025493 A 19931110