10

One point of note is that the yield region is not as cleanly defined as BCD is in the image (although most books have it that way). In reality the yield region looks like The following image is one from many actual measurement that I took years ago (its Force Displacement). You can see the jagged yield region after the elastic region. The point is that the ...


5

Point "C" is the "offset yield point" or "proof stress" as described below. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical ...


4

Yes; from B to C it is behaving elastically AND plastically. A small amount of plastic strain ( less than 0.2%) is mixed with elastic strain.


2

Summary: There is increasing plastic behavior and decreasing elastic behavior as the sample is strained from B to C. The transition is caused by random grain orientations and variable resolved shear stress. With respect, the other answers generally have the right idea, but are missing the important meso-scale mechanism for why there is a non-linear shape ...


2

Rubber is a hyperelastic material. It doesn't fall under the typical Ductile or Brittle categories. Percentage elongation and percentage reduction in length or area basically refers to permanent elongation or reduction, after the material has undergone any sort of plasticity (i.e. surpassing the yield strength of the material). If it experiences elongations ...


2

Generally what happens is that if when the load is removed (quasi statically) the material will return in a path which is parallel to the elastic region. Eg. for load up to E and F the following behaviour is observed. Notice that the slope of the red arrows is identical to the slope of OA section (region up to proportionality point). hysteresis If the load ...


1

Rather than getting hung up on the words, consider their usage. The authors' definition may only make sense in a specific context that that they were trying to convey. Ductile was about the ability to draw a material into a wire. The word or its roots may even preceed quantification of structural properties, but that's somewhat irrelevant. What is ...


1

Question 1: Elastic recovery will always take place until the material surpasses the Ultimate Tensile Strength (UTS) of it. This means that when ever you load a material and if it doesn't surpass its UTS, then it won't fracture but will be longer in length (in a Tensile loading) than its initial length when unloaded. Between B and C, the material is on the ...


Only top voted, non community-wiki answers of a minimum length are eligible