• 제목/요약/키워드: 레이저 홈가공

검색결과 11건 처리시간 0.015초

레이저 홈가공에서 편광빔의 다중반사 효과 (Effects of Multiple Reflections of Polarized Beam in Laser Grooving)

  • 방세윤;성관제
    • Journal of Welding and Joining
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    • 제23권2호
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    • pp.81-89
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    • 2005
  • 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.