Heterogeneous element distribution: a contribution to quantitative GDOS depth analysis

Summary The apparent enrichment of Cu, Mg, Mn and Si on the surface of Al cast-alloys, as observed by means of glow discharge optical emission spectrometry (GDOS), could be attributed to the heterogeneous distribution of the alloying elements. The samples under investigation were spectrochemical standards and hence assumed to be homogeneous. Different metallurgical phases were identified which induced selective sputtering. The findings point out that quantitative results obtained by GDOS in-depth analysis can be misleading and should be confirmed by other techniques such as Auger Electron Spectrometry and Energy Dispersive X-ray Spectrometry, which are free from sputter effects.