Learning Forum

[Rameez_ul_Haq]

If yes, then how can we be sure that this class of materials have a different Elastic modulus and strength in tension and compression? Or a material test is necessary to determine this?

[1shan]

Some time back I read about a class of materials called as Bimodular materials, which show different elastic moduli in tension and compression. Examples include a few elastomers, soft biological tissue, certain composites and rock like materials. You can have a look at these articles -
1. Sun, Jun-yi, et al. "A review on the research of mechanical problems with different moduli in tension and compression."Journal of mechanical science and technology24.9 (2010): 1845-1854.,
2. Bertoldi, Katia, D. Bigoni, and W. J. Drugan. "Nacre: an orthotropic and bimodular elastic material."Composites Science and Technology68.6 (2008): 1363-1375
3. C.W. Bert, J.N. Reddy, Mechanics of bimodular composite structures, in: Z. Hashin, C.T. Herakovich (Eds.), Mechanics of Composite Materials: Recent Advances, Proceedings of the IUTAM Symposium, Virginia Polytech. Inst., Blacksburg, VA, Pergamon, Oxford, 1983, pp. 323ÔÇô364
Regards Ishan.

[David Mercier]

Hi,
This question is related to the shape of the potential energy curve of atoms in close proximity. If you have a look on such curves, the shape is nearly symmetric in both tension and compression but most of the time only for small deformations. Here a reference paper about this: https://www.researchgate.net/publication/274434771_Potential_Energy_Curves_Material_Properties
And another example with this paper about biological tissues: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3099446/
Finally, this question is quite recurrent in the field of indentation testing, especially to know if indentation modulus is equal to tensile or bending Young's modulus:
And some information can be found in these AICs:
Regards

[1shan]

Thank you for adding some information to this discussion!!The articles are insightful.
Regards Ishan.

[Rameez_ul_Haq]

, thanks to both of you :)