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cassetteking

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Mar 26, 2025
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contradicting information is what I've gathered so far about mig welding with argon. some say it works fine, others say the welds are weak my old boss claimed you can use pure argon for steel but not the usual argon/co2 mix for aluminum. i've tried it and it seemed okay but how does it hold up strength wise? anyone tested this properly or is this just a gas supplier trying to upsell me?
 
yas! @cassetteking you can MIG weld with pure argon. however, it's not a good idea for steel cause it leads to poor penetration, cold welds, and a brittle weld profile. don't worry tho' you can use a mix of argon and an active gas like CO2 or oxygen
 
For aluminum, stick to pure argon (or argon/He), CO₂ on aluminum just blows through. If you want proof, weld up some test pieces and do a bend or pull test, you'll see the mixed gas steel welds hold way better.
 
contradicting information is what I've gathered so far about mig welding with argon. some say it works fine, others say the welds are weak my old boss claimed you can use pure argon for steel but not the usual argon/co2 mix for aluminum. i've tried it and it seemed okay but how does it hold up strength wise? anyone tested this properly or is this just a gas supplier trying to upsell me?
pure argon isn't recommended on steel, stick with an argon and CO2 mix. but, pure argon is the right choice for aluminum
 
contradicting information is what I've gathered so far about mig welding with argon. some say it works fine, others say the welds are weak my old boss claimed you can use pure argon for steel but not the usual argon/co2 mix for aluminum. i've tried it and it seemed okay but how does it hold up strength wise? anyone tested this properly or is this just a gas supplier trying to upsell me?
Using pure argon for MIG welding steel isn't the best choice. It can lead to shallow penetration and weak welds because of inadequate fusion between the metal and the filler material. Plus, the arc might be unstable. A better option for welding steel is a mix of argon and CO2, like a 75/25 ratio. This blend provides deeper penetration and results in stronger, more stable welds. If you're working with aluminum, pure argon works just fine, but when it comes to steel, it's best to go with that mix for optimal results
 
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