METHOD FOR QUANTITATIVELY DETERMINING MINUTE NONMETAL INCLUSION BY EMISSION SPECTRO ANALYSIS

摘要

PROBLEM TO BE SOLVED: To quickly and precisely perform the quantitative determination analysis of an inclusion having a particle size not larger than 1μm present in steel by determining the natural spectral line intensity value of oxygen in the first half part in every discharge, and arithmetically processing the resulting values to determine the quantity of a minute inclusion. ;SOLUTION: A spark discharge is performed between a metal sample 2 and a counter electrode 3, and the spectral line obtained by spectrally separating the emission in every spark discharge is detected by a detector 6 to measure the natural spectral line intensity of oxygen. In order to reduce the influence of a large particle size inclusion of 1μm or more, the natural spectral line intensity of oxygen obtained in every spark discharge is divided into a minute inclusion (the first half part of discharge time) and a large-sized inclusion (the latter half part) and measured. Only the natural spectral line intensity value in the first half part is used for the quantitative determination of the inclusion, the average value is compared with an analytical curve, and the natural spectral line intensity of oxygen in the first half part is further converted into frequency distribution. In this way, the quantitative determination of a minute inclusion (not larger than 1μm) in a metal material is quickly and precisely performed.;COPYRIGHT: (C)1997,JPO