| 摘要 |
PURPOSE:To enhance analytical preciseness, in the oxygen analysis in stainless steel, by a method wherein a vapor deposition film of Sn, Cu or Ag is preliminarily formed to the vapor deposition part of a graphite crucible for melting sample steel accommodated therein and the CO absorbing capacity of vapor deposited Mn is lowered. CONSTITUTION:After a graphite crucible is baked at 2,400 deg.C in air, Sn, Cu or Ag is introduced into the crucible and held at a temp. higher than that of the crucible at the time of analysis for a definite time to form a metal film of Sn, Cu or Ag on the wall of the crucible by vapor deposition. A stainless steel sample is charged into this crucible and a CO gas generated by melting is extracted by an Ar gas to be conveyed to an analytical system where CO is oxidized to CO2 to be subjected to quantitative analysis. Because Mn in the sample is vapor deposited to the wall of the crucible by the vapor deposition of Sn or the like to suppress the getter action thereof adsorbing CO, the measurement of O in the sample is carried out in good preciseness as well as the washing of the crucible for extracting CO or the exchange with a new one is reduced to a large extent and labor for disassembling and assembling an extraction furnace is reduced while rationalization of analytical work and cost reduction are attained. |
