×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*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.

Students Click Here

Jobs

Snap back or hysteresis

Snap back or hysteresis

Snap back or hysteresis

(OP)
Can someone tell me what the key physical property is for snap back or hysteresis of a material is?  I can find some correlation with durometer with LSR, but I was looking for a more accurate measurement then durometer.  Would modulus be more accurate?

RE: Snap back or hysteresis

On dynamically loaded parts, we tend to use ' loss angle' as a measure of internal damping (hysteresis).

Loss angle is defined as the phase lag between the applied load and the transmitted load through a rubber component, and is to a certain extent, dependent on dynamic amplitude and frequency.

Depending an the application, we also use dynamic stiffness as a measure of damping. Dynamic stiffness is the gradient of the  hysteresis loop produced during cyclic loading, and is also frequency/amplitude dependent. Dynamic stiffness is lowest at large amplitudes and low frequncy, and highest at small amplitudes and higher frequencies. Dynamic stiffness is always higher than the static stiffness.

These properties are dependent on material type and composition, but are not necessarily related to durometer.
60 shore natural rubber will generally have lower hysteresis than 60 shore chloroprene, for example.

If you need accurate dynamic data, you will need to perform  dynamic tests at a range of amplitudes and frequencies. Manufacturers of rubber antivibration mountings (including the one I work for) routinely produce this type of data.

I hope this helps

Tom

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.

Reply To This Thread

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

Click Here to join Eng-Tips and talk with other members!


Resources