“How can we measure when a deformation will be permanent on a material?”
When you were young, you probably noticed that if you apply enough stress onto an object, there will be a point in which in the material will be permanently deformed. However, did you ever consider that we might be able to classify this point in some form? Well, after many years of research, structural engineers have termed this “point of no return” as the yield. In technical terms, the yield point or yield strength is a material property that measures the point at which the level of stress applied becomes so high that the material will no longer deform elastically (meaning returning to it’s original shape) and instead deform plastically (meaning that there is some permanent deformation). The yield strength of an object is very important for estimating the applied strength it can take, since it could be used for pre-emptive failure analysis.