鋼中非金属介在物分析への冷硝酸法および冷硝酸アルコール法の適用

概要

論文の詳細を見る
An investigation has been made on application of the cold HNO_3 and cold HNO_3-alcohol methods to analysis of nonmetallic inclusions in steels. The results obtained are summarized as follows : (1) The changes of natural potential and temperature of the cold HNO_3 solution through the reaction with iron depend on the concentration of the cold HNO_3. According to the behavior of reaction with iron, the cold HNO_3 medium may be divided into 3 ranges, namely the high concentration range of (4+1)∿(1+1) at -15°∿-5℃, the medium concentration range of (1+3)∿(1+7) at -5°∿0℃, and the low concentration range of (1+9)∿(1+50) at 0°∿5℃. (2) The medium concentration range is most suitable for decomposition of Fe_3C, and the analytical condition of 200 ml (-5℃) of HNO_3(1+7) has been confirmed to be most recommendable for analysis of nonmetallic inclusions in killed steels (sample taken 1 g). (3) As compared with the cold HNO_3-H_2O system, the cold HNO_3-alcohol system has some different aspects ; the natural potential and the dissolving rate for iron are rather lower, but the low concentration range of the system can be applied even below 0℃ without freezing.
社団法人日本鉄鋼協会の論文
1975-10-01