THE INFLUENCE OF COBALT ON THE OXYSULFIDATION OF BRASS

The effect of Co on the oxysulfidation behaviour of vulcanized brass s heets has been studied by means of auger depth profiling combined with the statistical technique Maximum Likelihood Common Factor Analysis ( MLCFA). The chemical information, inherently present in the strongly o verlapping auger spectra, could be extracted by MLCFA and, hence, allo wed a detailed chemical characterization of the oxysulfidation layer a t the rubber brass interface. From this study it follows that Co acts as a selective diffusion barrier, promoting the growth of CuxS at the rubber interface, while retarding the ZnS production. Some aspects of this behaviour can lead to a better understanding of the oxysulfidatio n mechanism in the presence of ternary elements.