ND-YAG LASER WELDING PROCESS MONITORING BY NON-INTRUSIVE OPTICAL DETECTION IN THE FIBRE OPTIC DELIVERY SYSTEM

摘要

This paper describes a non-intrusive optical sensing technique for Nd:YAG laser welding monitoring. The cladding power monitor (CPM) detects the light returned through the cladding of the delivery fibre optic, and appropriate spectral filtering isolates the light radiated from the plume of hot gas which forms above the weld. The successful detection of welding faults using this optical signal is described, including laser focus errors and shield gas interruption. [References: 11]