Abrupt change of cross section in a member subject to load can result in

Explanation:

Stress concentration: 

• Stress concentration is defined as the localization of high stresses due to irregularities present in the component and abrupt changes in the cross-section. 

Causes of stress concentration:

Variation in properties of the material:

In general, the material is no homogenous throughout, there are some variations in the material properties due to the following factors:

• Internal cracks and flaws like blowholes.
• Cavities in welds.
• Air holes in steel components.
• Non-metallic inclusions.

These variations act as discontinuities in the component and cause stress concentration. 

Load application: The machine components are subjected to forces. These forces act either at a small or point area on the component. Since the area is small, the pressure at these points is excessive. This results in stress concentration. 

Abrupt changes in section: The abrupt changes are due to steps cut on the shafts to accommodate the bearings, pulleys sprockets. These create change in the cross-section of the shaft ad results in the stress concentration. 

Discontinuities in the component: There are some features of machine components such as oil holes, keyways, and splines, and screw threads result in a discontinuity in the cross-section of the component. There is stress concentration in the vicinity of these discontinuities. 

Machining Scratches: Machining scratches stamp marks or inspection marks are surface irregularities that cause stress concentration.