×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

 Forum Search FAQs Links MVPs

(OP)

The Stress values of a model with plasticity, material defined with a stress strain data, after yielding does not shows zero stress value after un-loading, although the elastic strain values goes to zero and plastic strain values is representing the Hysteresis loop.
At the zero load, the time history plot of stress should show zero stress.
The analysis of a small test model is done with Load step file, the first step is loading the model and the second step is un-loading the model with zero load applied.
The load applied is causing yielding and there are plastic strains at the notch of the model.

Thanks for input/help.

Well, the first thing that comes to my mind is that residual stresses might have developed in your model. It's quite normal since it happens in many physical processes.

(OP)
Yes, this is true, but what input for the FE analysis, is causing the program, to calculate the residual stresses?
The material model used in the analysis is Miso, with stress strain curve used.

I use this example when teaching nl fea.

Pipe with internal pressure above yield so the inner radius goes plastic. Unload that and the inner radius will go into compression. This is because outer radius material is elastic trying to go back during unloading thus squeezing inner radius into compression. This can be used to increase fatigue resistance.

This is also a good example:
https://www.comsol.com/blogs/model-residual-stress...

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

#### Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login

#### Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a partâ€™s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!