Yield Point - The load or stress at which a marked increase in the deformation of the sheet occurs without increasing the applied load. Yield point is one of the characteristics of low-carbon steels after they have been annealed. The yield point is usually calculated using a tensile-test specimen, and it is the load that is commensurate with the point beyond the elastic limit at which the specimen lengthens considerably without an additional increase in load.

Yield Strength - A value determined through actual destructive testing that indicates the amount of resistance to permanent deformation (bending). A material that is stressed to a point below its yield strength, will return to its original state when the stress is removed. A material that is stressed to a point beyond its yield strength will NOT return to its original state when the stress is removed. The higher the yield strength, the more resistance to bending a material exhibits.

Young’s Modulus - Same as modulus of elasticity.