Eutectic solidification characteristics of Bridgman grown Al-3Fe-0.1V alloy

Eutectic solidification characteristics of Al-2.85 wt % Fe-0.12 wt %V alloy have been investigated by steady-state growth over the range of solidifica tion front velocity from 51 to 1030 mu m/s and temperature gradient 8 to 15 K/mm. Increasing growth velocity displaced the alpha Al-Al3Fe eutectic by alpha Al-AlxFe eutectic rather than by the alpha Al-Al6Fe eutectic obtained for the binary Al-3 wt %Fe alloy. A fully alpha Al-AlxFe eutectic structur e has been obtained for the first time in the vanadium-containing alloy ove r the growth velocity range from 71 to 1030 mu m/s except at 100 and 510 mu m/s where some alpha Al dendrites were present in the eutectic matrix. The alpha Al-AlxFe eutectic was observed to undergo a morphological transition from lamellar to rod-like with increasing growth velocity concurrently wit h formation of a cellular eutectic structure. It was found that the relatio nship lambda = Av(-1/2), between eutectic spacing lambda and growth velocit y v, was applicable with A = 22.4 +/- 1.8 and 13.8 +/- 2.1 mu m(3/2) s(-1/2 ) for lamellar and rod-like alpha Al-AlxFe eutectics, respectively. (C) 199 8 Kluwer Academic Publishers.