Akademik Veri Yönetim Sistemi
Materials Characterization, cilt.62, sa.9, ss.844-851, 2011 (SCI-Expanded)
Al-11.1wt.%Si-4.2wt.%Ni eutectic alloy was directionally solidified upward at a constant temperature gradient (G = 5.82 K/mm) in a wide range of growth rates (V = 4.60-243.33 μm/s) and a constant growth rate (V = 11.63 μm/s) with different temperature gradients (G = 2.11-5.82 K/mm) by using a Bridgman type directional solidification furnace. The microstructure of directionally solidified Al-11.1wt.%Si-4.2wt.%Ni alloy was observed to be irregular plates of Al3Ni and Si within an α-Al matrix from quenched samples. The values of eutectic spacings (λSi and λ Al3 Ni) were measured from transverse sections of the samples. The dependency of λSi and λAl3Ni on the values of V and G was found to be λSi = 12.58V- 0.50, λAl3Ni = 7.94V- 0.47, λSi = 5.57G- 0.42 and λ Al3Ni = 4.31G- 0.45, respectively by using linear regression analysis. The values of bulk growth were also determined to be λSi2V= 170.52 and λ Al3Ni2V= 82.01 μm3/s by using the measured values of λSi, λ Al3Ni and V. The values of λSi and λ Al3Ni obtained in present work were compared with the values of λSi and λ Al 3Ni obtained in previous works for Al-Si and Al-Ni eutectic alloys. From the comparison, it can be seen that the values of λSi and λ Al3Ni for A1-Si-Ni eutectic alloy are smaller than the values of λSi and λ Al3Ni for A1-Si and A-Ni eutectic alloys under similar growth conditions. © 2011 Elsevier Inc.