초급냉응고한 Al-Cr 계 합금의 석출거동에 관한 연구 = A Study on the Behaviors for Procipitation of Super Rapidly Solidified Al-Cr Alloys

다국어 초록 (Multilingual Abstract)

The purpose of this paper was observation of and kinetic analysis of the precipitation process in heat-resistant alloys to improve the mechanical properties and the thermal properties. Al-Cr alloys were rapidly solidified into a ribbon shape by a melt spinner. The decomposition process of rapidly solidified Al-Cr alloys were examined by means of TEM, X-ray diffraction and micro-Vickers hardness. As a result of an isothermal aging of massively transformed Al-3.43wt.%Cr alloy at 450℃, subgrains formed by polygonization process. With more aging, precipitation occurred on the subgrain boundaries. The decomposition process of massively transformed Al-3.43wt%Cr alloy was analyzed by the cylindrical precipitation model. In the initial stave, n in the Johnson-Mehl-Avrami equation is 2.98 corresponding to the characteristics of the interface-controlled growth of a fixed number of particles. In the middle and the final stage, n is 1.85 corresponding to the characteristics of the diffusion-controlled growth of a fixed number of particles.

목차 (Table of Contents)

• 1. 서론
• 2. 실험방법
• 시료제작 및 열처리
• 조직관찰
• 미소경도측정
• 격자상수 측정
• 3. 실험결과
• 4. 결론