Abstract
During laser fusion cutting, burr forms when the molten metal does not sufficiently exit the interaction zone. When it forms on the lower edge of the cut flank, burr becomes a factor limiting quality. Previous research has shown that a temporally regular and spatially localized melt flow can prevent the formation of burr. However, the high dynamics of the subprocesses involved can cause intrinsic instabilities that disrupt the flow and reduce the efficiency of the melt ejection. This paper presents a study on the correlation between process parameters, melt flow properties, and burr formation. It includes an experimental observation of the melt-flow dynamics using high-speed videography. In addition, a Computational Fluid Dynamics model was set up to examine fundamental flow properties, some of which are not observable experimentally. The dependency of the burr formation on the liquid Weber and Reynolds numbers is analyzed, and it is demonstrated how the magnitude and allocation of vapor pressure gradients in the kerf decisively affect melt ejection and burr formation. Additionally, a previously unknown melt ejection regime is identified in the thick section range, which occurs at feed rates close to the maximum cutting speed under specific high-power process conditions. This regime is characterized by a significantly increased process efficiency that could open up a new high-speed process window.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.