MSA  Vol.11 No.8 , August 2020
Mechanical Properties of Remote-Laser Cut CFRP and Thermographic Laser-Process Monitoring
Abstract: Remote-laser beam cutting is a productive technology without tool wear. Especially when cutting carbon fiber reinforced polymers (CFRP), it offers constant manufacturing quality. Since it is a thermal process, a heat-affected zone (HAZ) is formed at the edge of the cut. Based on quasi-static and cyclic mechanical tests on open-hole specimens, the influence of the process on the mechanical properties of CFRP is shown. The quasi-static tests are in good correlation with results from other researchers by indicating an increase in the maximum tensile stress of the test specimens, cut by remote-laser. The reason is the rearrangement of the shear stresses and a reduction of the notch stress concentration. However, the results of the present study show that excessive expansion of the HAZ leads to a reduction in the maximum tensile stress compared to milled test specimens. Under cyclic load conditions, remote-laser beam cutting does not lead to a more pronounced degradation than milling. The mechanical properties of the notched test pieces are sensitive to the expansion of the HAZ. For the production of components it is therefore necessary that the remote-laser beam cutting is carried out under controlled and documentable conditions. For this purpose, process thermography was tested as a tool for quality assurance. The results show that the technology is basically suitable for this task.
Cite this paper: Rose, M. , Schettler, S. , Klemm, F. , Beyer, E. and Zimmermann, M. (2020) Mechanical Properties of Remote-Laser Cut CFRP and Thermographic Laser-Process Monitoring. Materials Sciences and Applications, 11, 560-575. doi: 10.4236/msa.2020.118037.

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