The Segregation of Bi and S from a Cu(Bi,S) Ternary System

J. J. Terblans, H. C. Swart
2009 e-Journal of Surface Science and Nanotechnology  
In this paper the ternary segregation behaviour of Bi and S in a dilute Cu(Bi,S) polycrystalline crystal was investigated by using Auger electron spectroscopy to monitor the surface concentrations of Bi and S during constant temperature segregation measurements that were preformed in the temperature range 723 to 973 K at 50 K intervals. It was found that initially both Bi and S segregated to the surface. At first the segregation rate of S was higher than that of Bi. The Bi segregated to the
more » ... gregated to the surface until it reached a surface maximum concentration (2-6%) and subsequently the segregation rate of both S and Bi decreased and the Bi started to desegregate. The S replaced the Bi completely on the surface. Diffusion parameters, namely the activation energy (Q) and pre-exponential factor (D0) were determined for Bi as 181.6 kJ·mol −1 and 3.7 × 10 −5 m 2 ·s −1 , respectively. The S concentration in the crystal was unknown and the S segregation profiles were used to estimate the S concentration in the Cu crystal as 122 ± 12 ppm.
doi:10.1380/ejssnt.2009.480 fatcat:bieeawp5sbcr3gkl653ehgd7ni