TY - CONF

T1 - Investigations on the thermal load and active thermal load reduction during laser processing of CFRP

AU - Staehr, R.

AU - Bluemel, S.

AU - Jaeschke, P.

AU - Suttmann, Oliver

AU - Overmeyer, Ludger

N1 - Funding information: The authors would like to thank the German Federal Ministry of Education and Research (BMBF) for funding these investigations within the project LaBoKomp (contract number 13N14111) and the VDI Technologiezentrum GmbH for their support.

PY - 2017

Y1 - 2017

N2 - This paper investigates the thermal load and the active thermal load reduction during laser drilling of CFRP using a nanosecond-pulsed high-power disk laser. The investigations employed different cooling configurations, applying active gas flow cooling to the test specimens. These arrangements involved cooling on the top surface only, cooling on both sides, the top surface and the bottom surface and no cooling applied as reference state. The top surface and bottom surface temperatures were measured by thermography during the laser processing of a multiple borehole pattern, supporting the evaluation of the cooling effectiveness. The heat affected zone (HAZ) of laser drilled cross-section specimens was measured, serving as an indicator for the thermal load brought into the material. The temperature and HAZ results were compared to laser processing without the use of active cooling for heat dissipation. The results revealed a distinct reduction in surface temperatures when gas flow cooling was applied to the top surface in comparison to processing without gas flow cooling. The surface temperatures were further reduced when gas flow cooling was applied to both the top and bottom surfaces of the test specimen. The evaluation of the HAZ revealed a good correlation between the cooling option, the temperatures measured and the resulting HAZ. The cooling method applying gas flow to both the top and bottom surfaces of the test specimen proved to be both simple and effective, significantly reducing the thermal load during laser processing of CFRP. This serves to minimize the delay times typically required for laser processing, thus leading to higher efficiency at a constantly low thermal load.

AB - This paper investigates the thermal load and the active thermal load reduction during laser drilling of CFRP using a nanosecond-pulsed high-power disk laser. The investigations employed different cooling configurations, applying active gas flow cooling to the test specimens. These arrangements involved cooling on the top surface only, cooling on both sides, the top surface and the bottom surface and no cooling applied as reference state. The top surface and bottom surface temperatures were measured by thermography during the laser processing of a multiple borehole pattern, supporting the evaluation of the cooling effectiveness. The heat affected zone (HAZ) of laser drilled cross-section specimens was measured, serving as an indicator for the thermal load brought into the material. The temperature and HAZ results were compared to laser processing without the use of active cooling for heat dissipation. The results revealed a distinct reduction in surface temperatures when gas flow cooling was applied to the top surface in comparison to processing without gas flow cooling. The surface temperatures were further reduced when gas flow cooling was applied to both the top and bottom surfaces of the test specimen. The evaluation of the HAZ revealed a good correlation between the cooling option, the temperatures measured and the resulting HAZ. The cooling method applying gas flow to both the top and bottom surfaces of the test specimen proved to be both simple and effective, significantly reducing the thermal load during laser processing of CFRP. This serves to minimize the delay times typically required for laser processing, thus leading to higher efficiency at a constantly low thermal load.

KW - CFRP

KW - Laser cutting

KW - Laser drilling

KW - Thermal load

KW - Thermography

UR - http://www.scopus.com/inward/record.url?scp=85053121301&partnerID=8YFLogxK

M3 - Paper

T2 - 21st International Conference on Composite Materials, ICCM 2017

Y2 - 20 August 2017 through 25 August 2017

ER -