Difference between stress- Strain Diagramm with von Mises Stress and Maximum Principal Stress

- October 25, 2019 at 8:39 am
  
  Hoosein86
  Subscriber
  
  Hello, I have Question about Stress-Strain Diagram with Max Principal Stress and von Mises Stress, could you please tell me why the curve at the Plastic part is not the same? Obviously the curve is at first diagram correct but at second Diagram not correct. You can see the Diagram below.
  
  Stress-Strain Diagram with Von Mises Stress:
  
  Stress-Strain Diagram with Max Principal Stress:
  
  Thanks for your helping.
- October 25, 2019 at 4:40 pm
  
  Sandeep Medikonda
  Ansys Employee
  
  Because, von-mises and principal stress definitions are quite different?
  
  See this.
- November 7, 2019 at 1:56 pm
  
  Hoosein86
  Subscriber
  
  Thanks for your answer, I read the Article but unfortunately I didn't completely understand, could you please explain base on the Grafiks that I show?
  
  Thank you.
- November 9, 2019 at 4:44 am
  
  peteroznewman
  Subscriber
  
  Create a Single Element model using a displacement on one face to create stress and strain in the element, then plot the different types of stress and see what the graphs look like then.