Question

The stress distribution in the metal after rolling is shown in the figure.



This condition where the surface has residual compressive stresses and the middle has tensile stresses can be produced by

• A. large diameter rolls and high reduction per pass
• B. small diameter rolls and small reduction per pass
• C. high rotation speed of rollers
• D. proper lubrication

Answer 1

The correct option is B small diameter rolls and small reduction per pass

Large diameter rolls and high reduction per pass produce tensile stress on the surface and compressive stress in the middle and vice versa for small diameter rolls or small reduction per pass.