Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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Effects of Multiple Reflections of Polarized Beam in Laser Grooving

레이저 홈가공에서 편광빔의 다중반사 효과

  • Bang Se-Yoon (Dept. of Mechanical Engineering, Dongguk University) ;
  • Seong Kwan-Je (Dept. of Mechanical Engineering, Dongguk University)
  • 방세윤 (동국대학교 공과대학 기계공학과) ;
  • 성관제 (동국대학교 공과대학 기계공학과)
  • Published : 2005.04.01
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Abstract

A numerical model for multiple reflection effects of a polarized beam on laser grooving has been developed. The surface of the treated material is assumed to reflect laser irradiation in a fully specular fashion. Combining electromagnetic wave theory with Fresnel's relation, the reflective behavior of a groove surface can be obtained as well as the change of the polarization status in the reflected wave field. The material surface is divided into a number of rectangular patches using a bicubic surface representation method. The net radiative flux far these patch elements is obtained by standard ray tracing methods. The changing state of polarization of the electric field after reflection was included in the ray tracing method. The resulting radiative flux is combined with a set of three-dimensional conduction equations governing conduction losses into the medium, and the resulting groove shape and depth are found through iterative procedures. It is observed that reflections of a polarized beam play an important role not only in increasing the material removal rate but also in forming different final groove shapes. Comparison with available experimental results for silicon nitride shows good agreement for the qualitative trends of the dependence of groove shapes on the electric field vector orientation.

Keywords

References

  1. W. W. Duley : Laser Processing and Analvsis of Materials, Plenum Press, New York, 1983
  2. 김도훈 : 레이저가공학, 경문사. 1992 (in Korean)
  3. F. Dausinger and T. Rudlaff : Novel Transformation Hardening Technique Exploiting Brewster Absorption. Proceedings of International Conference on Laser Advanced Materials Processing-Science and Applications, High Temperature Society of Japan. 1987, 323-328
  4. F. Dausinger, M. Beck, J. H. Lee, E. Meiners, T. Rudlaff and J. Shen : Energy Coupling in Surface Treatment Processes, Journal of Laser Applications, 2-3/4 (1990). 17-21 https://doi.org/10.2351/1.4745263
  5. S. Roy, S. Y. Bang, M. F. Modest and V. S. Stubican : Measurement of Spectral. Directional Reflectivities of Solids at High Temperatures between 9 and 11 ${\mu}m$, Applied Optics, 32-19 (1993). 3550-3558 https://doi.org/10.1364/AO.32.003550
  6. R. J. Wallace and S. M. Copley : Laser Machining of Silicon Nitride - Energetics. Advanced Ceramic Materials. 1-3 (1986), 277-283 https://doi.org/10.1111/j.1551-2916.1986.tb00029.x
  7. R. J. Wallace : A Study of the Shaping of Hot-Pressed Silicon Nitride with a High Power $CO_2$ Laser. PhD Thesis. Univ. of Southern California. 1983
  8. S. Y. Bang and M. F. Modest : Multiple Reflection Effects on Evaporative Cutting with a Moving CW Laser. ASME Journal of Heat Transfer. 113-3 (1991). 663-669 https://doi.org/10.1115/1.2910616
  9. S. Y. Bang, S. Roy and M. F. Modest : CW Laser Machining of Hard Ceramics - II. Effects of Multiple Reflections. Int. Journal of Heat and Mass Transfer. 36-14 (1993). 3529-3540 https://doi.org/10.1016/0017-9310(93)90170-B
  10. W. Schulz, G. Simon, H. M. Urbasseck and I. Decker : On Laser Fusion Cutting of Metals. J. Physics D: Applied Physics. 20 (1987). 481-488 https://doi.org/10.1088/0022-3727/20/4/013
  11. D. Petring, P. Abels and E. Beyer : Absorption Distribution on Idealized Cutting Front Geometries and Its Significance for Laser Beam Cutting. Proceedings of High Power $CO_2$ Laser Systems and Applications. SPIE. 1988. 123-131
  12. E. Beyer and D. Petring : State of the Art in Laser Cutting with $CO_2$ Lasers. Proceedings of the ICALEO 90. Laser Institute of America. 1990. 199-212
  13. W. Schulz and K. Behler : Adjustable Redistribution of the Laser Intensity between Teo Adjoining Metal Surfaces. High Power Lasers and Laser Machining Technology. SPIE. 1989. 166-172
  14. R. Siegel, J. R. Howell and J. Howell: Thermal Radiation Heat Transfer. 4th ed., Taylor and Francis Group. 2001La
  15. M. F. Modest : Radiative Heat Transfer. 2nd ed., Academic Press. 2003
  16. E. Hecht: Optics. 4th ed., Addison Wesley. 2001
  17. H. Kogelnik and T. Li : Laser Beams and Resonators, Applied Optics, 5-10 (1966). 1550-1565 https://doi.org/10.1364/AO.5.000005
  18. E. Waluschka : Polarization Ray Tracing. Proceedings of Polarization Considerations for Optical Systems. SPIE. 1988. 104-111
  19. I. D. Faux and M. I. Pratt: Computational Geometry for Design and Manufacture, Ellis Horwood Limited. U.K., 1979
  20. Kunwoo Lee : Principles of CAD/CAM/CAE Systems. Addison Wesley, 1999
  21. S. Roy and M. F. Modest : CW Laser Machining of Hard Ceramics - I. Effects of Three-dimensional Conduction, Variable Properties and Various Laser Parameters, Int. Journal of Heat and Mass Transfer, 36-14 (1993), 3515-3528 https://doi.org/10.1016/0017-9310(93)90169-7