ANALYSIS OF GASES IN ISON AND STEEL BY VACUUM FUSION METHOD

Abstract

Several furnace gases are dessolved in iron and steel during melting and contained as several compounds, blow holes, or solid solution after solidification. In the present work the analysis of these gaseous elements was carried out by the vacuum fusion method using a high frequency induction furnace. The extraction of gases contained in a graphite crucible to be used in the experiment and in vacuum furnace should be complete as possible and hence the graphite crucible is heated in vacuum at 1, 700°C for 3 hours under working of vacuum pump. In a blank test the amount of oxygen was decreased below 10mg as CO₂ in 15min. The amount of reduction of several oxide Fe₂O₃ MnO₂ SiO₂ Al₂O₃ was determined. The sample was introduced into the crucible heated at 1, 550°C and oxygen was extracted as CO. The oxygen in Fe₂O₃ and MnO₂ was extracted almost completely, but that in SiO₂ and Al₂O₃ about 96% and 86% respectively