The Modified Goodman diagram visually represents the safe operating envelope for components subjected to fluctuating stresses. Constructing this diagram within a spreadsheet program like Excel facilitates analysis of fatigue life under various loading conditions. This involves plotting mean stress on the x-axis and alternating stress on the y-axis, defining a region where failure is unlikely based on material properties such as ultimate tensile strength and endurance limit.
Creating such a diagram allows engineers to quickly assess the suitability of a material for a specific application involving cyclic loading. By comparing the calculated stress state of a component to the boundaries of the Goodman diagram, potential fatigue failures can be predicted and mitigated. This method offers a practical and accessible approach to fatigue analysis, particularly valuable in preliminary design phases or when specialized fatigue analysis software is unavailable. This type of analysis has evolved over time, originating from the work of Goodman and others who sought to provide practical methods for predicting failure under combined mean and alternating stresses. The adaptation of this method for spreadsheet software makes it accessible to a wider audience.
