Solidification Behavior of Ge-Al Eutectic Alloy in a Drop Tube


Erol M., BÜYÜK U.

TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS, vol.69, no.4, pp.961-970, 2016 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 69 Issue: 4
  • Publication Date: 2016
  • Doi Number: 10.1007/s12666-015-0592-y
  • Title of Journal : TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
  • Page Numbers: pp.961-970

Abstract

Drop tube processing was used to study rapid solidification of Ge-Al eutectic system. Liquid droplets with diameters in the range of 100-900 mu m were undercooled and containerlessly solidified in an 8 m drop tube. The cooling rate which plays a dominant role in structural morphology is estimated. The smaller the diameters of the droplets, the higher the undercooling and cooling rates. The eutectic reaction: L -> alpha(Al) + beta(Ge) was verified. Droplets larger than 500 mu m in diameter exhibited a complete coarse lamellar eutectics and regular dendritic structures. With the decreasing of the droplet size, lamellar eutectic to anomalous eutectic morphology transition took place. It was also proved that, higher undercooling caused lower eutectic spacing which affected the mechanical characteristics of materials like microhardness.