Microstructure and Corrosion Resistance of AZ91 Magnesium Alloy after Surface Remelting Treatment.

The effect of surface remelting treatment on the microstructure and corrosion resistance of the AZ91 magnesium alloy was studied. The surface layer was remelted by GTAW (gas tungsten arc welding). An original two-burner system with welding torches operating in a tandem configuration was used, allowing the combination of cleaning the surface from oxides with the remelting process.

Fractionation and mobility of Cu, Fe, Mn, Pb and Zn in the road dust retained on noise barriers along expressway - a potential tool for determining the effects of driving conditions on speciation of emitted particulate metals.

Road dust (RD) retained on noise barriers was used as a monitor of emission of traffic-related metals from expressway. By using SEM/EDX analysis it has been revealed that the main components of this particulate were irregular fine aggregates and tire debris with a ragged porous structure and with inclusions derived from the road surface. The results of chemical fractionation showed that driving conditions influence strongly a distribution pattern of Cu, whereas the atmospheric corrosion process affects a distribution pattern of Zn.