I have performed stress relaxation test on aluminum specimens and determined the values of Δσ, Δσ' and Δσ*. I want to find the stress relaxation rate and intrinsic height of thermally activated barrier. Anybody can help me please?
Regards.
I am familiar with stress relaxation in polymers only, but I believe that the principles are not too different. Probably the linearity range is different. In Polymers the stress relaxation tests are evaluated in the following way: the sample is deformed instantaneously and the force necessary to maintain the deformation is measured for a long time. The stress is calculated and a time dependent modulus is obtained which is plotted against log (time). The measurements are repeated at different deformations and temperatures. The linear rage is evaluated. The time dependent moduli measured at various temperatures are shifted along the log time axis to obtain a so-called "master curve" which can be fitted by various models and the shift factor is plotted against 1/T to obtain the activation energy of the process. (If it can be described by the Arrhenius equation).
Dear Sir, Thank you for you explicit response. Can you please refer me to the relevant article which you might have published somewhere. I think it will provide me a potential reference to cite in my article.
Best regards,
Mansoor
Dear Dr Mansoor, I have no publictions in this field, but I can mention here some articles to which you may refer:
http://www.unt.edu/LAPOM/publications/pdf%20articles/Time_temperature.pdf
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660009088.pdf
http://www.chem.mtu.edu/~fmorriso/cm4655/DealyPlazekTimeTempSuper2009.pdf
http://scitation.aip.org/content/aip/journal/jap/36/11/10.1063/1.1703022
For metals:
https://smartech.gatech.edu/bitstream/handle/1853/33859/krapf_carlyn_n_201005_mast.pdf;jsessionid=E1B10387DAE2153C5FEF93707F70645A.smart1?sequence=1
http://www.cmse.ed.ac.uk/PM2/PM2-Ch3.pdf
https://www.jim.or.jp/journal/e/25/02/89.html
http://www.viscodata.de/Short_Introduction.pdf
http://ocw.mit.edu/courses/materials-science-and-engineering/3-11-mechanics-of-materials-fall-1999/modules/visco.pdf
http://www.vtt.fi/inf/pdf/publications/2010/P728.pdf
From these references you can learn the technical detals as well.
Good luck!
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Physical Phenomena
- Luminescence
- Fluorescence