Lifetime models for high-temperature components

Components of engines and exhaust systems need to withstand severe cyclic mechanical and thermal loads during their lifetime. A method developed by Fraunhofer IWM for calculating the lifetime of thermomechanically loaded engine components is described. Low-cycle fatigue and thermo-mechanical fatigue tests were conducted on cast austenitic steel at different temperatures to determine the model parameters. Strain rate effects, stress relaxation and the cyclic hardening properties of the steel were investigated. Models for cyclic and non-isothermal viscoplasticity and microcrack growth were developed. The resulting model was used to predict the number of cycles to failure of a cast exhaust manifold using finite element simulations. There was good agreement between the predicted and measured numbers of cycles to failure.

  • Availability:
  • Authors:
    • SEIFERT, T
    • RIEDEL, H
    • PRAMHAS, G
    • BUMBERGER, G
  • Publication Date: 2007-2

Language

  • English

Media Info

  • Pagination: 34-8
  • Serial:
    • AUTOTECHNOLOGY
    • Volume: 7
    • Publisher: VIEWEG & SOHN VERLAGSGELLSCHAFT MBH
    • ISSN: 1616-8216

Subject/Index Terms

Filing Info

  • Accession Number: 01061006
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Sep 10 2007 2:01PM