Aluminium Welding Fume
Welding fume will be produced during welding of aluminium and its alloys. The fume is composed of particulate fume, which you can see, and gaseous fume, which you cannot see. Most of the particulate fume comes from the consumable. For all aluminium alloys any particulate fume produced during welding will be composed mainly of aluminium oxide. How much is produced depends largely on the process and the welding parameters being used. Inert gas shielded processes tend to generate ozone at high currents. MIG welding of aluminium will give particulate fume and ozone. Most ozone tends to be produced at high current, with aluminium-silicon filler wire, and in argon shielding gas. Aluminium-magnesium filler wires give less ozone but more particulate fume. TIG and plasma welding give very little particulate fume but can give ozone at high current using pure argon shielding gas. Helium-rich gas mixtures tend to give less ozone. MMA welding gives only particulate fume, comprising aluminium oxide plus fluorides and chlorides from the electrode coating. In general, with all these processes, the higher the welding current the more fume there is. Gas welding and gas brazing give rise to little fume and what there is tends to be fluorides and chlorides from the fluxes used with these processes. In terms of health effects the particulate aluminium oxide fume is not thought to be harmful but ozone certainly is.
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