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Saladsamurai
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Is there a difference, when looking at the stress-strain diagram, between the "Proportional Limit stress" and the "Yield Stress" ?
Thanks!
Thanks!
Hope this helps a little.A study of stress-strain diagrams shows that the yield point is so near the proportional limit that for most purposes the two may be taken as one. However, it is much easier to locate the former. For materials which do not possesses a well-defined yield point, one is actually "invented" by the use of the so-call offset method.
The yield stress is the point at which a material begins to permanently deform under stress, while the proportional limit is the maximum stress at which the material will behave elastically and return to its original shape when the stress is removed.
Yield stress is typically determined through tensile testing, where the stress is gradually increased until the material begins to deform. Proportional limit is determined by plotting the stress-strain curve and finding the point at which the curve becomes non-linear.
Yes, it is possible for the yield stress to be higher than the proportional limit. This usually occurs in materials with a large elastic range, where the proportional limit is lower due to the material's ability to withstand stress without permanent deformation.
Once a material is stressed beyond its proportional limit, it will begin to permanently deform. This means that even when the stress is removed, the material will not return to its original shape.
No, each material has its own unique yield stress and proportional limit, which are determined by factors such as composition, microstructure, and processing. These properties can also change under different environmental conditions, such as temperature and pressure.