In situ Observation of Calcium Oxide Treatment of Inclusions in Molten Steel by Confocal Microscopy

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Vol. 48; no. 3; pp. 1409 - 1415
• Main Authors: Khurana, Bharat, Spooner, Stephen, Rao, M. B. V., Roy, Gour Gopal, Srirangam, Prakash
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-06-2017; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Communication; Materials Science; Metallic Materials; Nanotechnology; Structural Materials; Surfaces and Interfaces; Thin Films; Inclusion Particle; Molten Steel; Cluster Behavior; Calcium Treatment; Liquid Steel
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-017-0956-2

Calcium treatment of aluminum killed steel was observed
in situ
using high-temperature confocal scanning laser microscope (HT-CSLM). This technique along with a novel experimental design enables continuous observation of clustering behavior of inclusions before and after the calcium treatment. Results show that the increase in average inclusion size in non-calcium-treated condition was much faster compared to calcium-treated condition. Results also show that the magnitude of attractive capillary force between inclusion particles in non-treated condition was about 10
−15
 N for larger particles (10 
µ
m) and 10
−16
 N for smaller particles (5 
µ
m) and acting length of force was about 30 
µ
m. In the case of calcium-treated condition, the magnitude and acting length of force was reduced to 10
−16
 N and 10 
µ
m, respectively, for particles of all sizes. This change in attractive capillary attractive force is due to change in inclusion morphology from solid alumina disks to liquid lens particles during calcium treatment.