Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Finite Element Analysis of Residual Stress Evolution during Cure Process of Silicone Resin for High-power LED Encapsulant

고출력 LED 인캡슐런트용 실리콘 레진의 경화공정중 잔류응력 발달에 대한 유한요소해석

  • Song, Min-Jae (Graduate School, Department of Mechanical Engineering, Korea Univ.) ;
  • Kim, Heung-Kyu (Molding & Forming Technology R&D Department, KITECH) ;
  • Kang, Jeong-Jin (Fusion Manufacturing Technology Department, KITECH) ;
  • Kim, Kwon-Hee (Department of Mechanical Engineering, Korea Univ.)
  • 송민재 (고려대학교 대학원 기계공학과) ;
  • 김흥규 (한국생산기술연구원 금형.성형연구부) ;
  • 강정진 (한국생산기술연구원 융합생산기술연구부) ;
  • 김권희 (고려대학교 기계공학부)
  • Received : 2010.09.14
  • Accepted : 2010.11.23
  • Published : 2011.02.01
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Abstract

Silicone resin is recently used as encapsulant for high-power LED module due to its excellent thermal and optical properties. In the present investigation, finite element analysis of cure process was attempted to examine residual stress evolution behavior during silicone resin cure process which is composed of chemical curing and post-cooling. To model chemical curing of silicone, a cure kinetics equation was evaluated based on the measurement by differential scanning calorimeter. The evolutions of elastic modulus and chemical shrinkage during cure process were assumed as a function of the degree of cure to examine their effect on residual stress evolution. Finite element predictions showed how residual stress in cured silicone resin can be affected by elastic modulus and chemical shrinkage behavior. Finite element analysis is supposed to be utilized to select appropriate silicone resin or to design optimum cure process which brings about a minimum residual stress in encapsulant silicone resin.

Keywords

References

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