Effects of Pouring Distance and Holding Time on the Thixotropic Microstructure of A357 Alloy


MATERIALS TESTING, vol.56, no.2, pp.111-117, 2014 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 56 Issue: 2
  • Publication Date: 2014
  • Doi Number: 10.3139/120.110532
  • Title of Journal : MATERIALS TESTING
  • Page Numbers: pp.111-117


Cooling slope casting process is one of the methods used to produce feedstock material having non-dendritic structure for thixocasting of A357 aluminum alloy. In the present work, the effect of various pouring distances of cooling slope on the microstructure of A357 aluminum alloy was investigated. For this purpose, the molten metal at 630 degrees C superheat temperature was poured on the surface of water-cooled slope. Reheating of feedstock ingots at a temperature of 572 degrees C with various holding times was also performed to achieve a spheroidal microstructure. Experimental results showed that optimum spheroidal microstructure of thixocasted A357 ingots having a cell size of 45 mu m and a shape factor of 0.60 of primary A were obtained when a pouring distance of 350 mm on the cooling slope is used. Al holding time of 5 min at 572 degrees C reheating temperature of feedstock ingots with 350 mm pouring distance provided optimum thixotropic properties.