가스분무성형 Cu-10Cr 합금의 열적응고거동 및 미세조직 = Research Papers : Solidification ; Solidification and Microstructure of Spray Formed Cu-10Cr Alloy

다국어 초록 (Multilingual Abstract)

The application of spray forming process to the fabrication of highly alloyed Cu-Cr materials has been considered in this study, in order to achieve a fine scale microstructure. Solidification and microstructural evolution of Cu-10Cr alloy during spray forming have been rationalized by quantitative analyses of average enthalpy and liquid fraction in the preform surface layer. The results gave an insight to establish quantitative guidelines for process optimization and to understand microstructural evolution during spray forming. The microstructure of spray formed Cu-10Cr alloy was characterized by an equiaxed cell structure in which smaller sized Cr particles were formed at Cu cell boundaries. In contrast, the ingot-cast billet had a dendritic microstructure comprising coarse primary Cr dendrites and fine Cu-Cr eutectic. The Cr particles had a good thermal stability in the Cu matrix because no significant growth occurred after exposure at elevated temperatures up to 900℃. After hot extrusion, the spray formed Cu-10Cr alloy had a good combination of strength and ductility.