Question

In reference to Young's modulus, what is post-yielding mean? I am doing a peer article review on hair and in the experiment stresses are applied to the hair in stage of plastic deformation (was able to figure out what that meant), in the plastic region befor post-yielding (sooo confused??), and then during post yielding. Cna you please break down these terms.

Answer 1

Each and every material has certain properties which can be assessed using stree-strain curve

Now,, the first step in this is the elastic limit during which a material will come back to its original shape or size. In this region, stress is direclty proportional to strain (strain is change in dimension over original dimension)

After that comes yield point, this is the point where a mateiral will have a permanent deformation means it will not regain its original shape. After some yield in the material, it will start to act as somewhat palstic and a point will come when an ultimate limit will reach which is also called as breaking or fracture point.