Metal Evaporation in GFAAS?
No, you do not evaporate the metals in question.  The use of aqua regia in the analysis aims to dissolve them, to form salts, which in turn are significantly more volatile than the metals or will decompose in the gaseous state.  (Just have a look alone at the melting points of the pure metals, which still are considerably lower than the boiling points, too.)

Without further detail about the colour of the "smoke", it remains a speculation that the sample placed on the L'vov plate still might have been a bit wet (from the acidic digestion).  If so, it were not good for the instrument, as it may lead to corrosion to metal parts of the housing around the graphite tube.