Schwarzkopf, K.; Rothfelder, R.; Rasch, M.; Schmidt, M. Two-Color-Thermography for Temperature Determination in Laser Beam Welding of Low-Melting Materials. Sensors2023, 23, 4908.
Schwarzkopf, K.; Rothfelder, R.; Rasch, M.; Schmidt, M. Two-Color-Thermography for Temperature Determination in Laser Beam Welding of Low-Melting Materials. Sensors 2023, 23, 4908.
Schwarzkopf, K.; Rothfelder, R.; Rasch, M.; Schmidt, M. Two-Color-Thermography for Temperature Determination in Laser Beam Welding of Low-Melting Materials. Sensors2023, 23, 4908.
Schwarzkopf, K.; Rothfelder, R.; Rasch, M.; Schmidt, M. Two-Color-Thermography for Temperature Determination in Laser Beam Welding of Low-Melting Materials. Sensors 2023, 23, 4908.
Abstract
Knowledge of the temperature evolution is crucial to understand and control laser beam welding of low-melting materials. Existing temperature determination approaches are restricted to i) one-dimensional temperature information (e.g. ratio-pyrometers), ii) a priori knowledge of the emissivity (e.g. thermography) and iii) high temperature regions (e.g. two-wavelength imaging). In this paper, a ratio-based two-color-thermography approach is developed that allows for two-dimensional temperature determination in low-melting temperature ranges (< 1200 K). For static measurement situations it is demonstrated, that temperature can be determined despite variation in signal intensity and emissivity with high accuracy. The two-color-thermography set-up is further transferred into a commercial laser beam welding machine and experiments are conducted for varying process parameters. The direct application of the developed two-color-thermography system in dynamic process situations is limited as image artifacts presumably caused by internal reflections inside the optical beam path are present.
Keywords
two-color-thermography; temperature; temperature determination; ratio-based temperature measurement; laser beam welding; low-melting materials
Subject
Engineering, Industrial and Manufacturing Engineering
Copyright:
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