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13-Aquamarine
January 21, 2013
Solved

Stress - strain curves & plasticity

  • January 21, 2013
  • 1 reply
  • 16676 views

Hello,

Should we use Engineering or True stress strain curves when carrying out plastic studies?

The material (for context) is steel.

I am assuming one requires True stress strain curves.

Thanks

    Best answer by TadDoxsee

    Hi Charles,

    Yes, the axis labels are incorrect in Creo 2.0 M030. They are corrected in M040, which should ship next month. Here's what it will look like.

    Tad

    Capture.PNG

    1 reply

    1-Visitor
    January 21, 2013

    When entering stress and strain data for elasto-plastic materials, be sure to enter true stress and true plastic strain (not engineering). Also, you need to enter the plastic strain not the total strain. The plastic strain is given by

    eps_pl = eps_tot - sigma / E

    where

    eps_pl is the true plastic strain,

    eps_tot is the true total strain,

    sigma is the true stress, and

    E is Young's moduls

    In Creo 3.0, we plan to change the interface so that the user enters true total strain instead of true plastic strain.

    Tad Doxsee

    PTC R&D

    346gnu13-AquamarineAuthor
    13-Aquamarine
    January 22, 2013

    It was a moment of self doubt when hunting down data to enter.

    Thanks for the confirmation.

    Charles