An analysis of the shearing stresses distribution on the cross-section of the twisted round bars

The state of stress generated by different loads represents an important factor that influences and determines the behavior and deforming capacity of the metallic materials or bars. This factor has a direct implication on the design and service of the machine components or structures. Its neglecting and, especially, its interaction with other factors can lead in certain unfavorable conditions and without visible deformations to instantaneous fracture, although the used materials satisfy the prescribed mechanical characteristics. Generally, the state of stress in a twisted bar is determined and conditioned by the twisting moment and angle of twist applied on the bar, the residual stress and, especially, by the shape and dimensions of the bar section. The present paper analyses the shearing stress distribution as a function of cross-section shape and dimensions for different twisted round bars.