EXPERIMENTS ON THE IMPROVEMENT OF ACCURACY OF SPECTROCHEMICAL ANALYSIS OF HIGH SPEED STEELS
HO I-DJEN;CHANG KUNG-SOO;LIU KUO-YU;WANG THANG-SOO;HSU SHENG-MEI Institute of Metal Research; Academia sinica
Cite this article:
HO I-DJEN;CHANG KUNG-SOO;LIU KUO-YU;WANG THANG-SOO;HSU SHENG-MEI Institute of Metal Research; Academia sinica. EXPERIMENTS ON THE IMPROVEMENT OF ACCURACY OF SPECTROCHEMICAL ANALYSIS OF HIGH SPEED STEELS. Acta Metall Sin, 1957, 2(2): 197-205.
Abstract In order to improve the accuracy of spectrochemical analysis of high speedsteels, a systematic study of the effect of different excitation conditions and di-fferent micro-structures of the samples on the accuracy of analysis has been made. A statistical study of the experimental error of single determinations showedthat the accuracy of a spark source was higher than that of an arc source, how-ever, this varied much with the different line pairs chosen. The slope (b) of thecalibration curves changed with current in an arc source and the value of b cameto a maximum when the current was in the neighborhood of one ampere. Apossible explanation of the appearance of such a maximum was given. In a sparksource it was found that the slope of the calibration curves of chromium or vana-dium decreased with an increase of the spark gap, but this was insignificant inthe case of tungsten. The effect of micro-structure of samples on calibration curves has also beenstudied. The standard samples of different structures (cast, hot forged and anneal-ed) were prepared for the present investigation. A parallel shift of calibrationcurves due to difference in micro-structure was observed in an arc source but notin a spark source. This type of shift can be explained by the facts obtained fromour previous work on the effect of micro-structure of steel samples on spectroche-mical analysis.