Abstract
Although there is no doubt about the tremendous industrial potential of metal additive manufacturing techniques such as laser metal deposition, the technology still has some intrinsic quality challenges to overcome before reaching its industrial maturity. Noncontact in-situ monitoring of the temperature evolution of the workpiece could provide the necessary information to implement an automated closed loop process control system and optimize the manufacturing process, providing a robust solution to these issues. However, measuring absolute temperatures is not self- evident: wavelength-dependent emissivity values vary between solid, liquid and mushy metallic regions, requiring spectral information and dedicated post- processing to relate the amount of emitted infrared radiation to the material temperature. This paper compares the temperature estimation results obtained from a VNIR hyperspectral line camera and a conventional SWIR thermal camera during the laser melting and cladding of a 316L steel sample. Both methods show agreeing results for the temperature distribution inside the melt pool, with the SWIR camera extending the temperature measurements beyond the melt pool boundaries into the solid region.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
