真空溶融法によるTi中O, Hの分析の精度と正確度に及ぼす諸要因の影響

抄録

In the previous report, the authors described that the vacuum fusion gas analysis using tin bath is an accurate and useful one for the simultaneous determination of oxygen and hydrogen in titanium. But it seems that papers on the influences of critical factors on precision and accuracy using the tin technique are scarce, so the authors have investigated about these influences and the following results were obtained: (1) It was ascertained that the operating temperature and the surface condition of graphite chips, especially its size, were the main critical factors for analytical procedures, and found that the most optimum conditions were 1920∼1950° and, 18∼20 mesh, respectively. (2) Solidification of bath and “gettering” action were observed, and we found both have tendency to decrease the rate of gas extraction. But useful techniques for restraining these influences have been found by the present authors. (3) The influence of Cl in Ti (produced by Kroll process) on the oxygen and hydrogen values was also discussed. (4) About 98% of oxygen was recovered by the proposed technique which gave about 5% deviation in the teems of coefficient of variance for 0.01% oxygen level, and about 8% for 0.001% hydrogen level. Morever, the lowest limit of determination were 0.003% for oxygen and 0.0002% for hydrogen.