Hi all
Is eg. 5083 (Al-Mg) much easier to Al-GMAW than 6000-series
(Al-Si-Mg)?
On 5083 I easily get really need welds, even if I say it myself.
On 6000-series the arc seems really fiesty. Welding 6000-series to
5083 it seems the 6000-series kick the arc off and the arc lands on
the 5083?
In other ways 6000-series seems like harder work to weld.
This fits with others' experience?

By the way - 3mm (1/8th-inch) thick 6000-series seems to be were the
most work is, as I've experienced so far ??

Best wishes,
Rich S

I forgot to say - GMAW wire is 1.2mm
(0.047")
5356

Hi again - what I'm finding on 6000-series alloys (typically
extrusions) is that as soon as you get into a real spray arc the arc
gets feisty - vivid colours, spitting and rasping, and if welding
6000-series to 5083, kicks sideways off the 6000-series onto the
5000-series.
Oh yes - and huge condensations of black powder around the welds
??
If you are in a lower power condition so you see Al depositing almost
like a stack-of-dimes, even if 5000-series to 6000-series, calm arc,
no misbehaviour and shiny silver welds metal and little condesation /
sooting around the weld. But - not much fusing power and you can be
left with re-entrant weld toes which look excessively like you are
risking cold laps.
??

Richard Smith <null@void.com> writes:

> Hi again - what I'm finding on 6000-series alloys (typically
> extrusions) is that as soon as you get into a real spray arc the arc
> gets feisty - vivid colours, spitting and rasping, and if welding
> 6000-series to 5083, kicks sideways off the 6000-series onto the
> 5000-series.
> Oh yes - and huge condensations of black powder around the welds
> ??
> If you are in a lower power condition so you see Al depositing almost
> like a stack-of-dimes, even if 5000-series to 6000-series, calm arc,
> no misbehaviour and shiny silver welds metal and little condesation /
> sooting around the weld. But - not much fusing power and you can be
> left with re-entrant weld toes which look excessively like you are
> risking cold laps.
> ??

For what it's worth - moved on further.
Getting things behaving well, doing Al-GMAW
Using 1.2mm wire 5183 wire (Al-Mg-Mn),
Spray is good - "just" at 10m/min, clean at around 12.4m/min and
smoothly in it goes for long runs at 15m/min.
Less than 10m/min - pulse. Totally sweet. 5000-series to 6000-series
no problem. Come a long way. Trust the synergic in pulse - easily
going from 5m/min to 8m/min for different thickness combinations and
joint geometries.
Getting into happy space.
This is talking about good industrial machines in a high-end metal
fabrications shop, by the way...

"Richard Smith" wrote in message news:lyczpitmjt.fsf@void.com...
....
> Oh yes - and huge condensations of black powder around the welds
> ??

------------

The black powder may be oxidized alloying elements. A quick test is to heat
it in the reducing portion of a propane flame. Copper oxide will revert to
the colored metal.