TY - JOUR A1 - Schmailzl, Anton A1 - Käsbauer, Johannes A1 - Martan, Jiří A1 - Honnerová, Petra A1 - Schäfer, Felix A1 - Fichtl, Maximilian A1 - Lehrer, Tobias A1 - Prušáková, L. A1 - Tesař, Jiří A1 - Skála, J. A1 - Honner, Milan A1 - Hierl, Stefan T1 - Measurement of Core Temperature through Semi-Transparent Polyamide 6 using Scanner-Integrated Pyrometer in Laser Welding JF - International Journal of Heat and Mass Transfer N2 - Predicting the core temperature during welding is an ambitious aim in many research works. In this work, a 3D-scanner with integrated pyrometer is characterized and used to measure the temperature during quasi-simultaneous laser transmission welding of polyamide 6. However, due to welding in an overlap configuration, the heat radiation emitted from the joining zone of a laser transmission weld has to pass through the upper polymer, which is itself a semi-transparent emitter. Therefore, the spectral filtering of the heat radiation in the upper polymer is taken into account by calibrating the pyrometer for the measurement task. Thermal process simulations are performed to compare the temperature field with the measured temperature signal. The absorption coefficients of the polymers are measured, in order to get precise results from the computation. The temperature signals during welding are in good agreement with the computed mean temperature inside the detection spot, located in the joining area. This is also true for varying laser power, laser beam diameter and the carbon black content in the lower polymer. Both, the computed mean temperature and the temperature signal are representing the core temperature. In order to evaluate the spatial sensitivity of the measurement system, the emitted heat radiation from both polymers is calculated on basis of the computed temperature field. Hereby it is found, that more than 90 percent of the detected heat radiation comes from the joining area, which is a crucial information for contact-free temperature measurement tasks on semi-transparent polymers. KW - Semi-transparent polymer KW - Pyrometer KW - Laser transmission welding KW - Temperature KW - measurement Y1 - 2020 U6 - https://doi.org/10.1016/j.ijheatmasstransfer.2019.118814 VL - 146 IS - January PB - Elsevier ER - TY - JOUR A1 - Quandt, Benjamin A1 - Schäfer, Felix A1 - Hierl, Stefan T1 - Heiße Infos aus schwachem Temperatursignal BT - Scanner-integrierte, pyrometrische Temperaturmessung für verstärkte Kunststoffe JF - Kunststoffe Y1 - 2018 SN - 0945-0084 IS - 12 SP - 65 EP - 68 PB - Hanser CY - München ER - TY - CHAP A1 - Schäfer, Felix ED - Mottok, Jürgen ED - Reichenberger, Marcus ED - Bogner, Werner T1 - Temperature Measurement with Scanner-Integrated Pyrometer during Laser Transmission Welding with Clearweld Absorber T2 - Applied Research Conference 2018, ARC 2018, 10 July 2018, Deggendorf Y1 - 2018 SP - 258 EP - 260 PB - pro Business GmbH CY - Berlin ER -