Compositional Changes During Electron Microprobe Analysis Of Alkali Silicate Glasses.

Local changes of compositions of alkali silicate glasses with time of electron bombardment during electron micro probe analysis are observed. The concentration of an element in the probed region varies with time in different ways depending upon the glass composition, the intensity of electron beam and the composition and thickness of conducting coating. The results are summarised as follows: Generally the xray intensities of the alkali metals is more rapid for higher beam loadings. Moreover, high beam loadings cause the increase of the xray intensities of the alkali metals in the low alkali glasses.