Before revision: The Goodman relation can be represented mathematically as: , where is the equivalent fatigue limit for combined alternating and mean stress , is the mean stress, is the fatigue limit for completely reversed loading, and is the ultimate tensile strength of the material .
After revision: The relations can be represented mathematically as: , Gerber Line(parabola), Goodman Line , Soderberg Line where is the stress amplitude , is the mean stress, is the fatigue limit for completely reversed loading, is the ultimate tensile strength of the material