the fatigue life of a material can be enhanced by which of t

the fatigue life of a material can be enhanced by which of the following techniques ?

a) cause hardening and introducing sharp corners

b) introduceing compressive stresses and sharp corners

c) cause hardning and shot peening

d) round corners and introducing tensile stresses

Solution

C)

Case Hardening and Shot Peening enhance the fatigue properties of a material.

Methods which increase the surface hardness(compressive strength) of the surface and also decrease the stress concentration( notch sensitivity ) are considered to improve fatigue life of materials.

examples are Carburizing, Nitriding, Shot Peening, Burnishing, Improve the fatigue life.

By process of elimination options a) b) and d) can be eliminated since they contain sharp corners,and tensile stresses respectively. Tensile stresses and sharp corners reduce the fatigue life of material.