Applied Physics A: Materials Science and Processing, cilt.95, sa.3, ss.923-932, 2009 (SCI-Expanded)
Al-Cu-Ag alloy was prepared in a graphite crucible under a vacuum atmosphere. The samples were directionally solidified upwards under an argon atmosphere with different temperature gradients (G=3.99-8.79 K/mm), at a constant growth rate (V=8.30 μm/s), and with different growth rates (V=1.83-498.25 μm/s), at a constant gradient (G=8.79 K/mm) by using the Bridgman type directional solidification apparatus. The microstructure of Al-12.80-at.%-Cu-18.10-at.%-Ag alloy seems to be two fibrous and one lamellar structure. The interlamellar spacings (λ) were measured from transverse sections of the samples. The dependence of interlamellar spacings (λ) on the temperature gradient (G) and the growth rate (V) were determined by using linear regression analysis. According to these results it has been found that the value of λ decreases with the increase of values of G and V. The values of λ 2 V were also determined by using the measured values of λ and V. The experimental results were compared with two-phase growth from binary and ternary eutectic liquid. © 2009 Springer-Verlag.