1964 Volume 50 Issue 6 Pages 904-910
The preparation, analysis, and microscopic examination of two series of ingots, made by adding oxygen and manganese or chromium to 6kg pure iron melt, are described.The analysis includes the chemical analysis of ingots, and chemical and X-ray analysis of non-metallic inclusions extracted by alcoholic-iodine or electrolytic method, and the estimation of chemical compositions of inclusions by an electron probe microanalyser.
The following results are obtained.
1) The product of deoxidation of iron by manganese is found to be a double oxide (Fe-Mn) 0, the composition of which varies continuously with increasing manganese content in an ingot.
The microscopic appearance of inclusions in polished metal section varies from round to irregular particle with increasing MnO content of (Fe-Mn) O.
2) The deoxidation product by chromium varies with chromium content in an ingot. FeO·Cr203 is formed in an ingot containing less than 5% Cr, and Cr203 is formed in one containing more than 5% Cr.Both of them have very similar appearance.
3) Though (Fe·Mn) 0 which is low in MnO is deformed a little, (Fe-Mn) 0 which is high in MnO, FeO·Cr203 and Cr2O3 is not deformed by hot working.