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Shape Casting pp 125-130 | Cite as

Ti Grain Refinement Myth and Cleanliness of A356 Melt

  • Özen GürsoyEmail author
  • Eray Erzi
  • Derya Dışpınar
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

Grain refinement of cast alloys provides several advantages such as establishment of finer dendritic structure, lowered porosity due to increased feeding, and thereby higher mechanical properties are reached. For Al–Si alloys, Ti is the preferred; however, Ti has the tendency to sink to the bottom of the crucible due to density difference. In this work, this phenomenon was used to evaluate the correlation of Ti nucleation on bifilms and thereby sedimenting the defects to clean the melt. Primary and secondary A356 alloys were used. After grain refinement addition, samples were collected every 10 min to investigate the change in melt quality. Sand and die moulds were used. Tensile samples were produced for mechanical characterisation. Step mould was used to check the microstructural changes. Reduced pressure test was used to quantify melt cleanliness. It was found that melt quality was increased by duration. Mechanical properties were increased regardless of the microstructure.

Keywords

Grain refinement Ti Melt quality Cleanliness Bifilm 

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.Metallurgical and Material Engineering DepartmentIstanbul University-CerrahpasaIstanbulTurkey

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