TWI Industrial Member Report Summary 909/2008
By S Shi and P A Hilton
Laser surface hardening was one of the first industrial applications of lasers and is rapidly developing as new and more cost-effective lasers, advanced laser optics and control systems, become available. The compact and energy-efficient direct diode lasers give a higher process efficiency and energy efficiency, making them more attractive to be integrated into a manufacturing line. The key factor for laser surface hardening is to maintain a constant surface temperature during the process. Variations in the surface temperature can cause fluctuations in the profile of the hardened layer. More recently, the development of new beam-forming optics and process monitoring systems has enabled the process to be controlled in real time to suit different industrial applications. Laser hardening parameters can be adaptively controlled based on the surface temperature of the sample and interactions between the laser beam and workpiece surface to achieve consistent surface properties.
This work therefore aims to assess the capabilities of laser surface hardening with adaptive control using a high power direct diode laser (HPDDL) and to establish the effect of laser parameters on the hardness profile of the hardened layer.
- Demonstrate the benefits of laser surface hardening with adaptive control of laser power.
- Establish the effect of laser parameters on the temperature and hardness profiles of the hardened layer.
- Establish the effect of material surface conditions on laser surface hardening.