Non-linear material data

[orac]

Hi there,

I'm looking for non-linear material data (e.g. Arruda-Boyce) for a standard polypropylene.
Anyone here who can point to the right direction where I can find these data.
I want to perform a large deformation calculation on a plastic part.

Thank you very much in advance.

Best regards,

John Bijnens
http://cad2cam.khlim.be



Edited by: orac

 

[TDPROE]

I can tell you mechanica is not the best choice for this type of analysis


some papers on the sbuject
http://www.springerlink.com/content/472430h313171154/

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi =B6TXX-4PB6VXN-1&_user=10&_rdoc=1&_fmt=&_ori g=search&_sort=d&view=c&_acct=C000050221&_ve rsion=1&_urlVersion=0&_userid=10&md5=ec32fd337d1 2fef0f1c4d9b2f685c56a

http://www.faqs.org/abstracts/Science-and-technology/Nonline ar-viscoelasticity-and-viscoplasticity-of-flax-polypropylene -composites.html

 

[andycph]

you can try this forum:

www.polymerfem.com

 

[Ray Ellender]

Dear Orac


To answer TD ProE's comment, I suspect he is not aware of the non-linear (hyper-elastic) properties in WF4 Mechanica, perhaps because you need the Asvanced licence. It is true that there are some limitations though (see PTC's info for these).


To answer your question, with WF4 you can put in coefficients such as Arruda-Boyce, but actually all you need is a stress-strain curve, and Mechanica will work out the best fit between a number of different models, inc Arruda-Boyce and calculate the coefficients for you. If you can't find a stress-strain curve for your grade of material (& there are so many grades, it is very unlikely that you will find the right curve in published data), then obtain a sample and have it tested, or 'invent' a curve from data that you probably can obtain, i.e, the initial modulus, the elongation and the ultimate strength. These give an initial slope and a final point; you just make a smooth curve in between and enter the data from it into Mechanica.


We have a training course on this if you need more help

 

[madscientist]

As your analyses become more critical and if have a particular material you wish to get non-linear data on, you may look intopurchase the material characterization data to help verify whatever material data you happen to be using. These are quite pricy, but the extra validation does increase the confidence in the analyses.


These usually cost about $4000 per data point from a variety of material testing labs such as datapoint labs, rapra, among others. You may be able to get some of this data from suppliers, but my luck has been most either don't have or don't choose to share it. You may have better luck.

 

[orac]

Thank you very much for the info.


I've solved my problem by letting perform a tensile strength test and used the data of that test for the simulation.