Directionally Solidified Structure and Mechanical properties in Monovariant Al - Fe - Ni - Eutectic Alloy
김두한Doo Han Kim, 이기대Kee Dae Lee, 조현기Hyun Kee Cho
Abstract
The variations of microstructure, interphase spacing and mechanical properties in Al-Fe and Al-Fe-Ni eutectic alloys have been investigated over a range of solidification rate from 1.2 to 38㎜/min under the thermal gradient of approximately 80℃/㎝. The results obtained are summarized as follows; 1. The coupled growth condition of aligned FeNiAl_9 phase was improved by Ni addition. 2. Increasing the solidification rate caused the transverse structure of Al-1.8% Fe-1.0% Ni alloy change gradually from non-cellular to elongated, square-cellular structure. 3. The relationship between the interphase spacing and the solidification rate was Rλ²=1.24×10^(-8)㎤/min. 4. The fracture occurred approximately on 45˚directions to the tensile axis.