Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
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The Estimation of Activation Energy for Prism Plane SliP {1120} <1100> Dislocation Velocity in Sapphire Single Crystals using Brittle-to-ductile Transition Model

취성-연성 전이 model을 이용한 사파이어 단결정의 prism plane slip {1120} <1100> 전위속도에 대한 활성화에너지 계산

  • Yun, Seog-Young (Department of Inorganic Materials Engineering, Pusan National University) ;
  • Lee, Jong-Young (Special researcher, Research Institute of Industrial Technology, Pusan National University)
  • 윤석영 (부산대학교 공과대학 무기재료공학과) ;
  • 이종영 (부산대학교 생산기술연구소 특별연구원)
  • Published : 2001.06.01
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Abstract

Experimental studies of the brittle-ductile transition (BDT) for pre-cracked sapphire single crystals were carried out. The BDT temperature in sapphire single crystals were $1000\pm$$25^{\circ}C$ and 1100$\pm$$25^{\circ}C$ at constant strain rate 3.3$\times$$10^{-5}$/sec and 3.3$\times$$10^{-6}$/sec, respectively. With aid of the BDT model, the activation energy for prism plane slip {1120} <1100> dislocation velocity was in the range of 4.6$\pm$2.3eV This activation energy for dislocation velocity with BDT model was compatible with the result of the dislocation velocity (3.8eV) using the etch-pit techniques.

사파이어 단결정의 취성-연성전이에 대한 실험을 행하였다. 사파이어 단결정의 취성-연성전이온도는 변형율 3.3$\times$ $10^{-5}$/sec에서 $1000\pm$$25^{\circ}C$ 그리고 변형률 3.3$\times$$10^{-5}$/sec에서는 1100$\pm$26$^{\circ}C$이었다. 취성-연성전이모델을 이용하여 Prism Plane slip {1120} <1100> 전위속도의 활성화에너지를 계산하였으며, 그 결과 활성화에너지는 4.6$\pm$2.3eV의 범위를 가졌다. 이 활성화에너지는 에치-퍼트법을 이용하여 전위속도측정으로부터 구한 결과치 3.8eV와 유사하였다.

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References

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