what the problem the work piece it black after welding?

[Iamtuaeng]

it’s just the appearance has something to do with oxidization maybe but we can not find out how it happen
our customer using same welding rods and we use same material come from the same supplier and we using same all processing for producing

W

 

[mike 109444]

Precleaning / degreasing BEFORE welding not the same ??

 

[voipio]

Are those parts welded or brazed?

 

[Iamtuaeng]

Precleaning / degreasing BEFORE welding not the same ??

we try everything but still same

 

[Iamtuaeng]

welded or brazed

welded....our product made from AL Alloy 6005A T6

 

[leadpig]

New batch of rods, rods damp?

 

[arther dailey]

looks like the first one has been sanded after welding , going by scratch marks , second one hasnt .

 

[snoozer]

Have you got a Picture of the Material BEFORE its Welded ?

 

[Memmeddu]

We Tig weld a lot of those AC pipes.
Never happened to us.
Discoloration make me think about lack of shielding gas