| Title |
A Study on the Microstructure of Spray Formed Al - Fe Alloys |
| Authors |
오규환(K . H . Oh); 김원태(W . T . Kim); 이호인(H . I . Lee) |
| Abstract |
The effects of melt flow rate and alloy composition on the microstructure of spray formed Al-Fe billets have been studied by using a combination of optical and transmission electron microscopy. Three transient regions in void distribution and solidification microstructure appear throughout the billet thickness : initial transient region dominated by chill effect by cold substrate ; quasi-steady state of microstructure beyond the initial transient region ; and final transient region due to decrease in melt flow rate. Large inter-connected void and fine microstructure developed first near the substrate and changes into different types of void and coarsened microstructure depending on thermal condition on the deposit top surface. In the deposit of Al-Fe alloy, monoclinic Al_(13)Fe₄precipitate is often observed with occasional observation of metastable orthorhombic Al_6Fe precipitate formed during flight. |