Closed loop control for laser micro spot welding using fast pyrometer systems

To stabilize the process we set up a power control for laser micro spot welding of copper. It consists of a high speed pyrometer and an external micro controller. The subject of the investigations is to apply a constant energy amount using conduction welding to increase the process stability. Using the closed loop control, the standard deviation of pull force for overlap welds is reduced from 3.3N to 1.3N.