Surface of Ally weld

[Paul G]

Hi All.

My ally welds have a weird suface appearance. The welds look sparkly for want of a better word.

Anyone seen this before? Any clues?

Cheers,
Paul G

 

[lincoln17]

Are you using pure argon and what flow rate are you set up at. Are there any draughts or air flow where you are working?

 

[hotrodder]

The grainy texture is due to the silicon in the filler wire, typically in conjunction with too much heat although some brands of wire are worse (more sensitive) than others. The harsher squarewave arc of inverters can exagerate the effect

 

[pedrobedro]

I have some 5356 wire that looks dull and bitty compared to the 4043 I have. The 4043 leaves a much brighter finish on the weld bead than the surrounding metal.

 

[hotrodder]

5356 wire that's been kicking around a little while will typically oxidise faster than 4043 i.e. a scotchbrite and solvent wipe will usually have a more noticable effect with 5356. The graininess in the pic is typical of AlSi wires when something isn't quite right (although AFAIK the grainyness itself is just a cosmetic thing). AlMg wires are a bit more prone to dull welds but if everythings right (good quality wire, shielding, heat input etc) ally TIG welds will be bright and clean regardless although there'll be slight variations in shininess with the different flavours i.e. AlMg won't be as shiney as AlSi which in turn will look a little dull compared with pure Al...



1050 wire on 1050



Can't remember and the rough polished tube skews the picture some but i suspect i probably used 5356 for that. Definately wouldn't have been 1050 due to the machined part

 

[Paul G]

The grainy texture is due to the silicon in the filler wire, typically in conjunction with too much heat although some brands of wire are worse (more sensitive) than others. The harsher squarewave arc of inverters can exagerate the effect

Interesting that you say this Hotrodder.

Base metal is 2mm 1050 sheet and the rod is 5% Si.
(Rolled to form a 2" filler neck in the top of a fuel tank.)
The welder is indeed an inverter, a Miller Dynasty.

I will do a test weld in the morning using base metal as the filler.

I will also make a note of the settings.

Thanks for all the replies.
Cheers
Paul G

 

[NTwoO]

So does one lessen the heat effect of the graininess by adding more amps and speeding up? I could for my life not get rid of the graininess in 4043. In turn, the 5356 welds look to have a creamy finish what I much prefer. I store my rods wrapped in plastic wrap. This is rather tightly wrapped, so the wrapping remains around the rods even after removing several. Only a small hole is required to remove rods.

 

[Paul G]

Rod test welds

Hi again.

I did some test welds using the following settings:-

Miller Dynasty 200.
pure argon @ 12 l/min. 15mm ceramic.
3mm white tungsten.
AC current. Amps set to max of 150. Foot control used so manual slope in/out.
Frequency 150.
65% ac balance.


Weld 1. Rod cut from edge of 2mm sheet.
Finish good.

Weld 2. Rod 4043 OK Tigrod
Finish was poor.


Weld 3. Rod was some old 1.6mm Sif 14 1050A that I've had for ages.
Finish was without doubt the cleanest. No surface sparkles at all.

See pic.


Well, you learn something every day, although several years ago I used a 3 phase Lincoln that had an auto balance setting, and I don't remember ever having a problem with suface finish no matter what the rod.
Shaky hands, watery eyes, I've got those, but nothing I can blame the welder on.

Many thanks to you all.
Paul G

 

[hotrodder]

So does one lessen the heat effect of the graininess by adding more amps and speeding up?

Possibly, it's more about the two being balanced than having to be able weld quickly but a slow move, pause and dip, move isn't going to help. If the welds are bright but grainy (like the pic in the OP) then arc length and heat are going to be pretty close- i'm thinking a tad cooler or faster might would have helped there

There seems to be a finer line to walk with inverters regarding grainy welds and AlSi wires. Never see any graininess on a casting repair when the machine is set with less %EN, sometimes see a little on a small fiddly sheet metal job. Less %EN and avoiding higher AC frequencies may help some

Ive got 2 maybe 3 different brands of 4043 around at the mo and a couple of 5356. One brand of 4043 is more prone to graininess than the other(s) and all of the Al wires from that manufacturer seem to have more contaminents/lubricants on them from drawing

 

[hotrodder]

Hey Paul,
1050 is a better choice for welding 1050 and 3103 than 4043 anyway. Save the 4043 for dissimilar welds (say like welding tank fittings machined from a 6xxx series alloy) although 5356 will work too

Have a play with the 4043 at different AC frequencies, i've found SIF to be one of the more grainy 4043 wires but as above it seems more forgiving when welding castings and i have the machine set closer to what you get out of a big ol' transformer

Oh, could also have a play with the AC waveform, can't remember if there's 4 choices with all the Dynastys' but i'd have thought a 'soft squarewave' would be better/more forgiving in this respect than the 'advanced squarewave'

 

[NTwoO]

Possibly, it's more about the two being balanced than having to be able weld quickly but a slow move, pause and dip, move isn't going to help. If the welds are bright but grainy (like the pic in the OP) then arc length and heat are going to be pretty close- i'm thinking a tad cooler or faster might would have helped there.

The idea about upping the amps and speed is cause I see that it reduces warpage and HAZ with Stainless. Whether it will help with alu is another question, since this is actually in the weld pool. Thanks in any case for the tip of lowering the freq and EN. This is invaluable information. Your contribution on the forum is most certainly heart warming and I've learnt so much from your posts. Thanks very much.