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Thermally-Induced Birefringence in Freely Quenched Plates of Polycarbonate

자유냉각된 폴리카보네이트 평판에서의 열에 의한 복굴절

  • 이호상 (충주대학교 항공.기계설계학과) ;
  • Published : 2007.06.01

Abstract

Simulations of the thermally-induced residual stresses and birefringence in freely quenched plates of polycarbonate were performed by using the linear viscoelastic and photoviscoelastic constitutive equations for the mechanical and optical properties, respectively, and the first order rate equation for volume relaxation. The predictions for the birefringence showed good agreement with experimental measurements. However, for initial temperature close to the glass transition temperature, some differences existed around the surface layer. Based on the simulation, the influences of various cooling conditions on the residual stress and birefringence in plates were investigated. The residual stress and birefringence increased with increasing initial temperature, decreasing coolant temperature and increasing heat transfer coefficient of coolants.

Keywords

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