High-speed thermal cameras enable in situ measurement of the temperatures in and around melt pools generated during powder bed fusion processes. These measurements can be used to validate models, to monitor the process, and to better understand material transformations that occur during the process. Unfortunately, pre-placed powder layers complicate the measurement due to spatter and irregular surfaces that impact emissivity. The objective of this work is to present high speed thermographic measurements of single and multiple scan tracks on substrates with and without pre-placed powder and to discuss the impacts of powder on the measurement of melt pool length and cooling rate.
Proceedings of the Solid Freeform Fabrication Symposium
August 7-9, 2017
Solid Freeform Fabrication Symposium
Additive manufacturing, powder bed fusion, thermography, temperature, melt pool length, cooling rate, emissivity, powder