평면상 응고계면의 형태학적 안정성에 대한 비평형 열역학적 고찰 = A Nonequilibrium thermodynamic Approach to the Morphological Stability of solid-Liquid Interface

다국어 초록 (Multilingual Abstract)

This theoretical study was carried out on the determination of the morphological stability criterion of planar solid-liquid interface. The system of a directional solidification under the nonequilibrium steady-state was defined as a continuous open system and the basic assumptions for the perturbation on the planar interface were introduced in order to analyze the pattern formation. The pattern formation was also interpreted by applying the marginal stability hypothesis. The results obtained can be summarized as follows.
1. The morphological stability criterion was T_mΓω²+ G_L-mG_c $gt; 0 and this could be reduced to the CS criterion.
2. The critical wavelength of perturbation, λ_c, was calculated by applying the marginal stability. From this result, it could be predicted that the shapes of the interface were changed with the wave length of perturbation.
3. It was suggested that the cell size, ℓ, can be limited by the critical wavelength of perturbation.

목차 (Table of Contents)

• 1. 서론
• 2. 비평형열역하적 안정성기준
• 3. 응고계의 구성
• 3.1 연속개방응고계의 모델
• 3.2 섭동의 도입
• 4. 안정성함수의 유도
• 4.1 응고계의 과잉앤트로피생성
• 4.2 응고계면 주위의 온도와 농도
• 4.3 응고반응의 excess force
• 4.4 안정성 함수, f(ω)
• 5. 응고계면의 안정성
• 5.1 평면상 응고계면의 안정성 기준
• 5.2 평면상 응고계면의 한계안정성
• 6. 결론