FACTOR OF STRESS CONCENTRATION
During the design phase of an engineering component, it is critical to consider safety parameters that define the efficiency of the mechanism. Basic stress analysis and calculations are performed at the initial phase assuming the components are smooth, having uniform profile and without irregularities. However in actual, all engineering components have at least minimal changes in section and/or shape like shoulders /steps on shafts, holes for oil, key ways and screw threads, which can impact on distribution of stress, some example figures are shown below.
Mathematical analysis of stress concentration
Discontinuities in the components that lead to local increase of stress is referred to as stress concentration. Stress concentration factor (Kt), is a dimensionless factor which is used to quantify how concentrated the stress is in a material. It is thus defined as a ratio of the highest stress in the element to the reference stress. So it is important to analyze the component for stress concentration in order to have proper functioning of the component with safety. Otherwise the fabricated/manufactured component will not be fully functional with load; this might further hamper the balance of the system and cause severe effects.
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