Rapid Determination of Small Amount of Carbon on Steel Making Process by Emission Spectrometric Analysis

Abstract

A rapid determination method of small amounts of carbon on steel making process by emission spectrometric analysis was studied. In this study, the influence of sample surface and measurment conditions on an analytical value were made clear. The followings results were obtained.
(1)ZrO₂ abrasive paper was better than Al₂O₃ one for the surface preparation of sample concerning analytical precision, while the grit size of polisher had no influence on analytical results.
(2)A sample surface of small amount carbon had a thin and smooth layer by electrical spark remelting compared with an high carbon steel sample, therefore it results in necessity of less time for pre-spark-burn.
(3)Regarding the carbon spectral line for analysis, C( I ) 165.8 nm was appropriate for the range below 0.01% content and C( I ) 193.1 nm was better for the range over 0.01%.
(4)Interference for the carbon spectral by coexisting elements were not observed, however the presence of Al₂O₃ inclusion had influence on the carbon intensity. The interference might not be reduced without the classification technique of calibration curves.