ISIJ International
Online ISSN : 1347-5460
Print ISSN : 0915-1559
ISSN-L : 0915-1559
Experimental Studies on Al2O3 Inclusion Removal from Steel Melts Using Ceramic Filters*
Klaus RaiberPeter HammerschmidDieter Janke
Author information
JOURNAL FREE ACCESS

1995 Volume 35 Issue 4 Pages 380-388

Details
Abstract

Filtration tests were made on Al-deoxidized iron melts in a 50 kg vacuum induction melting and casting unit using commercial foam, multi-hole and loop filters. Samples from the solidified metal were prepared for chemical analysis and quantitative metallography. Al2O3 inclusions were produced by the addition of pure Al to the oxidized metal. Filtration efficiencies based on the content of chemically analysed total oxygen or oxide particle size distribution were evaluated.
Filtration of pure iron melts using ceramic foam filters reaches efficiencies up to 90%. A minimum of total ixygen content around 20 to 30 ppm is attained independent from the initial oxygen content of the melt. The lowest levels are achieved when 25 ppi foam filters are applied. Filtration tests using 100 cpsi multi-hole filters for pure iron reveal filtration efficiencies of 80% and total removal of inclusions larger than 20 μm in diameter. Filtration efficiencies of 72 to 84% for pure iron were obtained using ceramic loop filters of different string diameters. From the evaluation of volume flow capacities and filter resistances it was evident that casting time is prolonged up to the threefold as compared to casting tests without integrated filters.
Filtration of steel melts using ceramic foam, multi-hole or loop filters is an effective tool. High separation efficiencies are achieved, but filtration capacities of the porous filter media are limited in view of large steel volumes.

Content from these authors
© The Iron and Steel Institute of Japan
Previous article Next article
feedback
Top