Question

How does shot peening prevent the fatigue cracks from growing?

Answer 1

• Shot peening is a cold work process used to finish metal parts to prevent fatigue and stress corrosion failures and prolong product life for the part. In shot peening, small spherical shot bombards the surface of the part to be finished. The shot acts like a peen hammer, dimpling the surface and causing compression stresses under the dimple. As the media continues to strike the part, it forms multiple, overlapping dimples throughout the metal surface being treated. The surface compression stress strengthens the metal, ensuring that the finished part will resist fatigue failures.
• Shot peening is the most economical and effective method of producing and making surface residual compressive stresses to increase the product life of treated metal parts. Shot peening is also used for work hardening to improve wear characteristics, straightening distortions, surface texturing and for creating aerodynamic curvatures for aerospace designs. The increased strength of treated parts allows for lighter-weight parts that exhibit high wear and fatigue resistance.