Author:

Keywords:

Inclusions, PDA-OES, Inclusion extraction technique, ULC steel

Abstract:

On the basis of PDA-OES data, two methodologies to determine the inclusion size were proposed viz. (i) obtaining the average inclusion size by dividing the insoluble Al quantity by the number of Al based inclusions and (ii) obtaining the inclusion size distribution from the individual Al peak intensity data. The inclusion size evolution in ULC steel was studied on the basis of these proposed methodologies and the inclusion extraction technique. The increase in the average inclusion size from Tundish (1) to Tundish (3) sample was in good agreement with each other for all methodologies/techniques. The comparative study of the average inclusion size measured for the three tundish samples was not in close agreement with each other. The possible causes for the discrepancies have been summarized. The present work leads to the following conclusions 1) The average inclusion size calculated on the basis of PDA-OES data is found to be greater than the average inclusion size measured by the inclusion extraction technique. 2) The number of inclusions in the ablated volume could be more in number than that determined by the PDA-OES as far as inclusions smaller than 2 μm are concerned. The role of submicroscopic inclusions in the PDA-OES analysis is not clearly understood.