Determination of Liquid Metal Quality with Deep Etching Method

  • Furkan Tezer
  • Özen Gürsoy
  • Eray Erzi
  • Mert Zorağa
  • Derya DışpınarEmail author
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


In this study, the deep etch method was applied to Al–Si casting alloys in order to visualize the presence of the bifilms. Reduced pressure test was used to quantify the bifilms in the melt. The cross section of the RPT samples was subjected to deep etching with H2SO4, HNO3, NaOH, and NaCl solutions at various temperatures and concentrations. The aim was targeted to etch the matrix and reveal bifilms on these surfaces. Additionally, the oxide structure on the surface of cast specimens was altered by treatment at 500 °C for 8 h. One half was ground, and these samples were subjected to deep etching again in the same conditions. It was found that bifilms were dissolved after 5 min of deep etching in HNO3, H2SO4, NaCl, and NaOH solutions.


Deep etch Bifilm Liquid metal quality Porosity 


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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Furkan Tezer
    • 1
  • Özen Gürsoy
    • 1
  • Eray Erzi
    • 1
  • Mert Zorağa
    • 1
  • Derya Dışpınar
    • 1
    Email author
  1. 1.Engineering Faculty, Metallurgical and Materials Engineering DepartmentIstanbul University CerrahpasaAvcilar, IstanbulTurkey

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