Recent developments in three-dimensional laser machining

Abstract

A concept for three-dimensional laser machining which allows implementation of turning, milling, and threading processes is presented. The primary aspect of the three-dimensional process is the laser grooving process. This paper discusses some issues relating to the material removal rate, surface quality, and process control for laser grooving. For laser grooving of ceramics, the use of an off-axial gas jet to remove molten material is studied under different laser operating parameters. The off-axial jet is found to improve laser machining effectiveness and surface quality by creating a large pressure gradient at the erosion front which expels molten material from the front of the groove and increases grooving effectiveness. For laser grooving of composites, a concept for using a water jet in tandem with the laser beam to reduce thermal damage is introduced. The water jet serves as a source for dissipation of conduction heat through boiling heat transfer. A scheme for process control of laser grooving using feedback of acoustic emissions is also discussed. A closed-loop control scheme is shown to significantly improve transient response and reduce the effects of process disturbances.A concept for three-dimensional laser machining which allows implementation of turning, milling, and threading processes is presented. The primary aspect of the three-dimensional process is the laser grooving process. This paper discusses some issues relating to the material removal rate, surface quality, and process control for laser grooving. For laser grooving of ceramics, the use of an off-axial gas jet to remove molten material is studied under different laser operating parameters. The off-axial jet is found to improve laser machining effectiveness and surface quality by creating a large pressure gradient at the erosion front which expels molten material from the front of the groove and increases grooving effectiveness. For laser grooving of composites, a concept for using a water jet in tandem with the laser beam to reduce thermal damage is introduced. The water jet serves as a source for dissipation of conduction heat through boiling heat transfer. A scheme for process control of laser grooving usi...