The load per unit of original cross section at which, in soft steel, a marked increase in deformation occurs without increase in load.
The stress (load/area) at which the metal changes from elastic to plastic in behavior, i.e., takes a permanent set.
The coefficient of elasticity of stretching. For a stretched wire, Young’s Modulus is the ratio of stretching force per unit cross-sectional area to the elongation per unit length. The values of Young’s Modulus for metals are of the order 10 12 dynes per square cm. (See Modulus of Elasticity)