Temperature field based closed-loop control of laser hot wire cladding for low dilution

Abstract

A modified laser hot wire cladding process is demonstrated with beam oscillation for high productivity and low dilution. A 2-channel pyrometer camera is used to observe the melt pool geometry during process to evaluate the current status of the process. Deviations from a set optimum are recognized and automatically compensated by a laser power control. A comparison of uncontrolled and controlled cladding process shows a significantly lower standard deviation of the dilution compared to the uncontrolled cladding process. The experiment verifies a relation of penetration depth and melt pool length.