合金钢的组织结构对於光谱分析的影响

我们用爱氏光源(低电流交流电弧)作高速钢的光谱分析时,发现样品的组织结构对于分析结果有影响。为了对这个现象得到进一步的了解,我们选择了10种含碳量不同的铬钢进行热处理试验和光谱分析。一系列实验的结果指出,用小电流(5安)电弧光源时,铬的光谱分析结果由于试样是退火组织或淬火组织而有差别,这个差别又随着钢中含碳量的增加而增加。我们认为,这种影响是由于碳在试样中存在状态的不同所引起的。在低功率光源中,这种不同使合金元素被蒸发和被激发的情况有所差别,因而就影响了光谱分析的结果。这种影响由于合金元素之不同而有程度上的不同,对铬的影响很显著,对锰和矽的影响则很小。此外,所选择的分析线对是弧线还是火花线,对于这种组织结构的效应也有显著的影响。曾经进行了一些消除组织结构影响的实验。发现在应用低功率光源时,增加预燃时间并不能消除这个效应。用火花光源或大电流(8安)电弧光源时,这种影响大为减小。

EFFECT OF MICRO-STRUCTURE OF THE SPECIMEN ON THE SPECTROCHEMICAL ANALYSIS OF ALLOY STEELS

In the spectrochemical analysis of high speed steels with a small current activated a.c. arc (after Aбрамсон), the results of analysis were found to be affected by different previous heat-treatments given to the steel samples. To study this effect we selected 10 chromium steel samples of different carbon content. Spectrochemical analysis of these samples under different procedures of heat treatment shows that with an a.c. arc (5 amp.) the results of analysis of Cr for annealed and for hardened samples of the same steel are different and the difference increases with the increase of carbon content. We are inclined to think that in a low energy light source, the evaporation and the excitation of the alloying elements vary according to the existing form of carbon and this directly affects the results of spectrochemical analysis. The magnitude of this effect is different for different alloying elements, it is considerable in the case of Cr but is inappreciable in the case of Mn and Si.How to eliminate the effect of micro-structure on spectrochemical analysis was also investigated. It was found that with a low energy light source, the effect can not be eliminated by increasing the time of pre-arcing. However, this effect is considerably reduced by using a spark source or an a.c. arc source of large current.