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In automated machining processes, long and continuous chips often cause machine down and hence increase process cost. Chip control or chip breaking methods are essential for unattended and automated systems such as CNC metal cutting machine or other fully automated metal cutting machines, especially for those which are integrated into production line. Conventional metal cutting chip control relies on the knowledge of chip flow angle, chip curl and breakage. In this paper, a new concept of metal cutting chip breaking using laser energy is presented and discussed. Preliminary laser chip breaking for copper, aluminum and steel was investigated under static conditions by using a commercially available pulsed Nd:YAG laser. The results showed that the effectiveness of chip breaking by lasers varied dramatically at different levels of laser energy with or without assisted blow-off air.

Laser welding has long been evaluated as a joining technique for galvanized steels in a lap-joint configuration in the automotive industry. However, a problem associated with the low boiling point of zinc limits the application of the laser process in a lap-joint configuration. Zinc-coatings at the interface of the two coated sheets vaporize during welding and the volume of the zinc vapor expands rapidly. The venting of the zinc vapor from the weld pool causes expulsion of the molten metal during welding and a portion of zinc vapor remains in the weld as porosity after welding. To improve the weld quality of galvanized steel, many efforts have been attempted worldwide, but limited success has been reported. Edison Welding Institute (EWI) investigated the laser weldability of galvanized steel in a lap-joint configuration with no gap using a dual beam laser welding technique.