The evaporation rates and mechanisms of cadmium from a bubble-stirred molten copper bath

Experiments to determine the evaporation rates and aerosol formation mechan ism of cadmium in molten copper at atmospheric pressure have been carried o ut. A small amount of cadmium (similar to1 wt pet) was added to molten copp er at 1473 K and allowed to evaporate while bubbling 750 and 1500 cm(3)/min of argon through the melt. Melt samples were periodically taken and analyz ed by inductively coupled plasma/mass spectroscopy (ICP/MS) to determine th eir impurity content. A theoretical model to predict the evaporation rates of solutes from molten metals was developed and compared to the experimenta l results. Excellent correlation between experiment and theory was found fo r the cadmium-copper system. The model has been extended to other solutes a nd also to molten Fe-3 (wt pct) C at 1873 K as a solvent.