Brad93
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- Essex, United Kingdom
2ppmI read an extremely informative and interesting post @backpurge wrote about a tiny amount of O2 added to a Ar/He mix under a tig arc which by definition would be TAG. He linked a video to it iirc showing the tiny amount of O2 acting as an arc stabiliser. I’ve forgotten the %ratio but we are talking very small amounts and not enough to oxidise the tungsten.
Yeah exactly that's classed as TAG whereas is that mix was used gmaw it would be mig. I remember working at this place welding 30mm plate something like inconell 725 or high cromo. Was this weird Argon,nitrogen blend and the arc was all over the place you had to take a break it sounded awful and no chance of a pretty weld.
The nitrogen is used to promote austenite formation. Doesn’t add anything to the weldability, as you say probably welded crap.