Microstructure-bifilm interaction and its relation with mechanical properties in A356

TUNÇAY T., TEKELİ S., ÖZYÜREK D., Dışpınar D.

INTERNATIONAL JOURNAL OF CAST METALS RESEARCH, cilt.30, sa.1, ss.20-29, 2017 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 30 Sayı: 1
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1080/13640461.2016.1192826
  • Dergi Adı: INTERNATIONAL JOURNAL OF CAST METALS RESEARCH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.20-29
  • Anahtar Kelimeler: A356, Cooling rate, SDAS, Porosity, Mechanical properties, Bifilm, FE-RICH INTERMETALLICS, TENSILE PROPERTIES, MELT CLEANLINESS, AL-7SI-MG ALLOY, ALUMINUM-ALLOYS, METAL QUALITY, RUNNER SYSTEM, CAST ALLOYS, POROSITY, IRON
  • Gazi Üniversitesi Adresli: Evet

Özet

Cooling conditions and inclusions are of the most important factors that affect mechanical properties of cast aluminium alloys. This study investigated the effect of secondary dendrite arm spacing (SDAS) on the shape of pores (i. e. bifilm unravelling) and the mechanical properties of cast A356 alloy. Different cooling conditions were established by electrolytic copper chill, H13 steel chill and insulated ceramic that was placed in the mould cavity. SDAS and shape of pores were investigated by optical microscopy. The fracture surfaces of tensile test samples were analysed by SEM and EDX. Weibull two-parameter statistical method was used to assess the tensile properties. Results show that mechanical properties were dominantly affected by pore morphology that was formed by bifilms. Increasing the cooling rate (i. e. decreasing SDAS), the unravelling of bifilms delayed which decreased porosity formation significantly.