A 4-color imaging pyrometer was developed to investigate the thermal behavior of laser-based metal processes, specifically laser welding and laser additive manufacturing of stainless steel. The new instrument, coined a 2x pyrometer, consists of four, high-sensitivity silicon CMOS cameras configured as two independent 2-color pyrometers combined in a common hardware assembly. This coupling of pyrometers permitted low and high temperature regions to be targeted within the silicon response curve, thereby broadening the useable temperature range of the instrument. Also, by utilizing the high dynamic range features of the CMOS cameras, the response gap between the two wavelength bands can be bridged. Together these hardware and software enhancements are predicted to expand the real-time (60 fps) temperature response of the 2x pyrometer from 600 °C to 3500 °C. Initial results from a calibrated tungsten lamp confirm this increased response, thus making it attractive for measuring absolute temperatures of steel forming processes.

Date Published: 11 May 2016
PDF: 8 pages
Proc. SPIE 9861, Thermosense: Thermal Infrared Applications XXXVIII, 986103 (11 May 2016); doi: 10.1117/12.2223083

Published in SPIE Proceedings Vol. 9861:
Thermosense: Thermal Infrared Applications XXXVIII
Joseph N. Zalameda; Paolo Bison, Editor(s)