pISSN : 1598-706X / eISSN : 2288-8381
한국주조공학회지 (29권2호 64-69)
Influence of Cooling Rate and Alloy Composition on The Microstructural Evolution of Al-Ag Eutectic System
Al-Ag2Al 공정계 합금의 조성 및 냉각 속도에 따른 미세조직 고찰
Sung-Woo Sohn*, Jin-Man Park*/**, Tae-Eung Kim*, Ka-Ram Lim*, Won-Tae Kim***, Do-Hyang Kim*
*Yonsei University, **IFW-Dresden/ Institute for Complex Materials, ***Cheongju University
In the present study the effect of cooling rate during solidification on the microstructural characteristics of Al-xAg (x = 31, 33, 35 at.%) in-situ binary eutectic composites has been investigated. To provide a wide range of cooling rate three different casting techniques, i.e. conventional casting, injection casting, and melt spinning have been used. The observed microstructure is very much dependent on the cooling rate. The fcc α-Al and hcp Ag2Al phases exhibits an orientation of (111)Al//(0001)Ag2Al, [1- 10]Al//[11-20]Ag2Al. The microstructure of the melt-spun samples contains Widmanstätten structure resulting from solid-state transformation and nano scale two-phase structure resulting from solid-state phase separation. The microstructure of injection- cast samples contains eutectic structure and solid state phase-separated structure. On the other hand, conventional-cast samples exhibit a microstructure consisted of plate-type eutectic structure.
Al-Ag2Al eutectic, Eutectic alloy, In-situ eutectic composite, Phase transformation.