極低酸素鋼中のアルミナ介在物の粒度分布測定法

抄録

A technique for particle size distribution measurement of Al₂O₃ inclusion in ultra low oxygen steel by combination of ultrasonic classification method and centrifugal sedimentation photo-extinction method has been established.
The procedure is as follows.
(1) The Al₂O₃ inclusion extracted from steel by acid decomposition is classified at over and under 5μm with ultrasonic filtration.
(2)The Al₂O₃ inclusion over 5μm is weighed.
(3) The particle size distribution of Al₂O₃ inclusion under 5μm is measured automatically with centrifugal sedimentation photo-extinction method.
(4)The particle size distribution of Al₂O₃ in steel can be obtained by using from (1) to (3).
This technique makes it possible to measure particle size distribution of Al₂O₃ to sub-micron order, and gives instructive information about coalescence and/or floating behavior of Al₂0₃ inclusion during refining prosess.