Global Patent Index - EP 1714717 A1

EP 1714717 A1 20061025 - Method of predicting damage of dies

Title (en)

Method of predicting damage of dies

Title (de)

Verfahren zur Vorhersage des Versagens von Matrizen

Title (fr)

Méthode de prédiction de la défaillance des matrices

Publication

EP 1714717 A1 20061025 (EN)

Application

EP 06008110 A 20060419

Priority

JP 2005120660 A 20050419

Abstract (en)

Disclosed is a method of predicting damage of dies for plastic processing of metallic materials, typically, forging dies, by predicting brittle fracture ("great crack" or "initial crack") dominating die lives contribute to die design including choice of materials, hardness and configuration of the die. The method is characterized in that the die design is carried out by choosing the condition that none of the anticipated values of brittle fracture, F c1 to F c3 , calculated by the formulae 1 to 3 below exceed the critical values depending on the material used. [ formula €‰ 1 ] €‰ F c 1 = ( à m / à e q ) [ formula €‰ 2 ] €‰ F c 2 = ( à m / à 1 max ) [ formula €‰ 3 ] €‰ F c 3 = ( à 1 max / à e q ) à m : mean normal stress loaded to the tensile side of the die à eq : Von Misese's equivalent stress à 1max : maximum principal stress

IPC 8 full level

B21J 13/02 (2006.01); B22C 9/06 (2006.01)

CPC (source: EP US)

B21J 13/02 (2013.01 - EP US)

Citation (search report)

  • [DA] PATENT ABSTRACTS OF JAPAN vol. 2003, no. 03 5 May 2003 (2003-05-05)
  • [A] PATENT ABSTRACTS OF JAPAN vol. 2000, no. 12 3 January 2001 (2001-01-03)
  • [A] PATENT ABSTRACTS OF JAPAN vol. 2002, no. 05 3 May 2002 (2002-05-03)
  • [PA] KIM ET AL: "Estimation of die service life against plastic deformation and wear during hot forging processes", JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, ELSEVIER, AMSTERDAM, NL, vol. 166, no. 3, 20 August 2005 (2005-08-20), pages 372 - 380, XP005023923, ISSN: 0924-0136

Designated contracting state (EPC)

DE FR GB IT

Designated extension state (EPC)

AL BA HR MK YU

DOCDB simple family (publication)

EP 1714717 A1 20061025; EP 1714717 B1 20080402; DE 602006000842 D1 20080515; DE 602006000842 T2 20090520; JP 2006297429 A 20061102; JP 4556753 B2 20101006; US 2006230881 A1 20061019

DOCDB simple family (application)

EP 06008110 A 20060419; DE 602006000842 T 20060419; JP 2005120660 A 20050419; US 40637906 A 20060419