SHOT PEENING OR LASER PEENING: A COMPARATIVE GUIDE TO THEIR APPLICATION(S)
What is the Difference in how Shot Peening & Laser Peening are Applied?
- Shot Peening is performed with a nozzle or wheel such that there are thousands of impacts per second, using shot ‘media’ such as glass, ceramic or metal balls.
- Laser Peening creates a pressure wave for spot-by-spot application at up to 10 spots per second. Spot sizes can be adjusted.
Laser peening is digitally applied, that is for each and every laser shot the irradiance of that position is specifically controlled
What is the Main Difference in the Residual Stress From the Processes?
- Laser peening is a deep compressive stress process that achieves 5x-10x the depth of shot peening.
When Does One Consider Laser Peening a Solution Over Shot Peening?
- When failures require a very deep layer of compressive stress such as foreign object damage, severe fretting, corrosion fatigue or stress corrosion cracking.
- When contamination is an issue – no residual ‘shot’ or contamination with laser peening.
- When normal or near normal incidence application is not possible.
- For elevated temperature applications of super-alloy components including IN718, AM material and single crystal material: LP + TME (developed by Curtiss-Wright) has been shown to increase fatigue strength and fatigue life.
- If shot peening is unable to achieve desired fatigue performance, laser peening can be considered.
When Does One Consider Shot Peening a Solution Over Laser Peening?
- Shot peening is a mature technology having been in existence for over 50 years and is used in all industries with metal parts in fatigue loading.
- Shot peening is a lower cost process with more job shop and equipment choices.
Are There Tools Laser Peening Uses That Shot Peening Doesn’t?
- Finite Element Analysis is used to strategically engineer the laser peen optimal spot pattern.