J Mater Sci Technol ›› 2009, Vol. 25 ›› Issue (03): 395-400.

• Research Articles • Previous Articles     Next Articles

Dynamical Solidification Behaviors and Metal Flow during Continuous Semisolid Extrusion Process of AZ31 Alloy

Renguo Guan1)†, Liqing Chen2), Jiangping Li1), Fuxing Wang1)   

  1. 1) School of Materials and Metallurgy, Northeastern University, 3-11 Wenhua Road, Shenyang 110004, China
    2) The State Key Laboratory of Rolling and Automation, Northeastern University, 3-11 Wenhua Road, Shenyang 110004, China
  • Received:2008-01-28 Online:2009-05-28 Published:2009-10-10
  • Supported by:

    National High-Tech R&D Program of China (Grant No. 2007AA03Z111),
    Natural Science Foundation of China (Grant No. 50604007)
    New Century Excellent Talents in University (Grant No. NCET-06-0285 and NCET-08-0097).

Abstract:

In this paper, a novel near-net-shape forming process, continuous semisolid extrusion process (CSEP) of AZ31 alloy was proposed, and the dynamical solidification behaviors and metal flow during the process were firstly investigated. During casting AZ31 alloy by this process, non-uniform microstructure distributions and non-equilibrium solidification region near the roll surface were found in the roll-shoe gap. Microstructural evolution from dendrite to rosette and spherical grains was observed during the casting by CSEP. Casting temperature, roll-shoe gap width and cooling ability have great effect on casting process and metal flow, so these factors should be carefully controlled, a proper casting temperature of 710×750°C is suggested. The white ® phases were strongly stretched during the processing, and the remnant liquids are correspondingly distributes along the solid phase boundaries and also show stripped lines.

Key words: Dynamical solidification, Continuous semisolid extrusion process, Micro structural evolution, AZ31 alloy