|MadSci Network: Chemistry|
The most common gases used for gas shielded arc welding are inert gases Argon (Ar) and Helium (He). It is very common to use mixtures of these gases, and also add other gases such as Oxygen (O2) and Carbon Dioxide (CO2). I have seen some experimental mixtures that incorporated Nitrogen dioxide (NO2), but they are not commercially available as it is too toxic for domestic use. If you want to get more information I can recommend The Welding Institute (http:\\www.twi.co.uk) who have online tutorials on all aspects of welding, and BOC Gases (http:\\www.boc.com\gases) who don't have much online information, but used to publish a very good information pack on welding gases. You may be able to get them to send you one if it is still in print. Good luck with the essay, Krystal.
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