Metallurgical Transactions

, Volume 2, Issue 10, pp 2825–2828 | Cite as

Modified stress-strain relation for FCC metals and alloys

  • D. C. Ludwigson
Mechanical Behavior


The flow curve of some metals in the region of uniform plastic deformation can be expressed by the Ludwik model, σ=Kn. For stable austenitic stainless steels and other face-centered-cubic (fcc) metals with low stacking fault energies, a second term has been added to the Ludwik model to account for devitations at low strains. The modified model \(\sigma = K_1 \in ^{n_1 } + e^{K_2 } \cdot e^n e^ \in\) adequately describes the plastic flow of these materials. The value for σ at ε=0 in this model ise K 2 and agrees reasonably well with the observed proportional limit. It is hypothesized that the modification term accounts for transient planar flow of dislocations favored by low stacking fault energy.


Stable Austenitic Stainless Steel 


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Copyright information

© The Metallurgical Society of American Institute of Mining, Mitallurgical and Petroleum Engineers, Inc., and American Society for Metals 1971

Authors and Affiliations

  • D. C. Ludwigson
    • 1
  1. 1.Applied Research LaboratoryUnited States Steel CorporationMonroeville

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