A Comparative Study on Microstructure Properties of AZ91 Magnesium Alloy with Silicon Addition Using Ceramic Mold


Gören H. A. , Ünal M. , Koç E.

8thInternational Advances in Applied Physics and Materials Science Congress Exhibition, Muğla, Türkiye, 24 - 30 Nisan 2018, ss.118

  • Basıldığı Şehir: Muğla
  • Basıldığı Ülke: Türkiye
  • Sayfa Sayıları: ss.118

Özet

In this study, comparatively microstructure and hardness properties of AZ91 alloy with the a ddition of 1.95 wt.% silicon were investigated by using ceramic mold. For this purpose, the alloys were provided to solidfy in different rates owing to use that mold. Alloys poured into this mold showed a rapid cooling behavior due to copper in the base, while cooling rate decreased on the top zone. The results showed that α+Mg main matrix phase is present in AZ91 structure, Mg-Al eutectic and Mg17Al12  intermetallic phases extending along grain boundaries were observed in the main  matrix  as  well.  As  the  cooling  rate  increases,  the  grain  boundaries  of  Mg17Al12  intermetallic  phases  were increased. The Mg17Al12  phase at grain boundaries was partially fragmented by the addition of Si. Coarsen Mg2Si phases  were  also  formed  with  the  addition  of  1.95  wt.%  silicon.  The  hardness  values  were  increased  with  the increasing of cooling rate and the addition of silicon.