Product Code: ICAL08_1901

Laser Peen Forming for Non-thermal 2D Shaping and Micro Adjustment of Sensitive Metallic Components
Authors:
Kenneth Edwards, The University of Liverpool; Liverpool Great Britain
Stuart Edwardson, The University of Liverpool; Liverpool Great Britain
Christian Carey, The University of Liverpool; Liverpool Great Britain
Geoff Dearden, The University of Liverpool; Liverpool Great Britain
Ken Watkins, The University of Liverpool; Liverpool Great Britain
Craig Williams, University of Liverpool; Liverpool Great Britain
Presented at ICALEO 2008

Laser peen forming has been carried out on steel, stainless steel, copper and brass samples, with thicknesses ranging between 0.03 and 0.3 mm, using an Nd:YAG (pulse length 8ns, at 10hz) laser at 1064nm wavelength. The process was found to produce bending in all materials and thicknesses tested, with the non-thermal process, which is backed up with finite element modeling of the process. The results from these experiments have been compared to samples formed using continuous wave thermal forming, and show that the laser peen forming does not create a heat affected zone or changes to the bulk material, seen with laser thermal forming. This indicates that the laser peen forming process is largely athermal, as there is very little heat input into the samples except for decolorisation of the surface due to the plasma generated in the process. This has been backed up by thermocouple measurements and laser beam interaction experiments. The effect that the process has on the surface of the material is also being analysed using optical interferometry and scanning probe microscopy.