スパークイオン源質量分析法の鉄鋼の微小部分析への適用

抄録

A mass spectrographic apparatus equipped with a triggered DC spark source has been developed for an effective microprobe analysis of scores of micron diameter on the surface of steel and the other alloys. The purpose of the present investigation is to analyze trace elements whose contents are less than the detection limit of electron probe microanalyzer, in microscopic area smaller than usual by adjusting a spark gap by an optical microscope, which is installed in the spark source unit of a mass spectrograph.
As the results, the size of crater created by spark is about 30 u in diameter for the exposure of 1×10^-12 coulomb, which is much smaller than that obtained with a spark gap by direct visual observation. The reproducibility of ion intensity detected in the proposed technique is about 10% for almost all the elements, being similar to that by direct visual observation. This technique is also applied to a segregation analysis of welding posts of carbon and high alloy steels and dross in zinc plating bath, and some interesting informations are obtained about the segregation of trace elements in the above materials.