Study and control process in laser conduction welding for millisecond pulse duration range

摘要

A new system has been built allowing the fast control of the laser welding process in conduction regime. Based on a traditional Proportional Integral Derivative (PID) analysis, the system can regulate millisecond laser pulse (Its response time is 90 microseconds). Besides, the interaction in this regime has been monitored with different diagnostics. Visible signal above target, IR signal from surface and visualization from CCD camera have been correlated as function of laser power density to distinguish the different phases of interaction (pure conduction, vaporization and/or plasma). With this experimental set up, the detector used for control process could be calibrated. The integration of the system is shown for watch parts assembly.