CONSTANTIN APOSTOL, MIHAI BUTU, CRISTIAN DOBRESCU, ALEXANDRA TACHE RESEARCHES REGARDING THE REDUCTION OF OXIDATION LOSSES IN THE OBTAINING OF SECONDARY ALUMINIUM ALLOYS USING METALLIC SCRAPS
The paper presents thermodynamic aspects regarding the low temperature processing of small metal waste - aluminum alloy scraps. The activation energies of oxidation reactions of aluminum and some alloying elements with water vapors, carbon dioxide and oxygen present inside the furnace are compared, at the usual and experimentally temperatures (at 580 – 620oC, near the eutectic temperature, when the melt is in the semisolid/pasty state), in the elaborating of EN AB 46100 secondary alloys. The composition of the flue gases is presented at different temperatures and during different technological stages. Using electronic microscopy and EDS analysis, the elemental composition of the impurities resulted from the melt is highlighted.
Keywords: metallic scraps, secondary Al alloys, activation energy, oxidation