Aluminum bronze is stronger so better for repairs that need strength. Its also better for salt water and acidic environments. Welds better on AC, so if you have a DC only welder you may be better off with silicon bronze. Silicon bronze flows easier, and has more appealing aesthetics. So if you want the gold color to show for whatever reason, you are probably better off with SilBro. SilBro also works much better on DC. I would use SilBro on any bushing type applications.

There are also dissimilar metal combinations that are better off with one or the other. I don't remember what they are, but you can google the charts on the interwebs.SilBro get used an awful lot for body work, especially in a MIG type application. SilBro is also much better when joining galvanized metal.

 

If you are going to stock only one rod out of the 2 I would highly recommend A2 for repair work.

 

My current machine is DC only. So sounds like that may be a limiting factor.

 

You won't be disappointed with only having SilBro at first.

 

A2 welds just fine on DC. Slight soot.

 

Thanks everyone. I'm trying to build my filler rod stock up in order of usefulness. 10lbs of er70s 3/32, 10lbs of er70s 1/16, 5 lbs er70s .045 (which made all the difference between 1/16 filler in .050 sheet metal) , 1 lb 316l . Next is aluminum or silicon bronze. Just chipping away as cash allows. Now I'm out of argon and have to wait a few until I can get a fill up. What other types of filler do you recommend for DC tig welding? Im thinking some 308 will be next.

 

Im thinking some 308 will be next.

If you have 316 then you don't need 308, 316 will cover for 304 and 316 SST

 

If you are looking to do repair work and you have such an extremely limited budget I would recommend you purchase 4943 aluminum filler before you ever buy silicon bronze or aluminum bronze. Now my recommendation could be inappropriate but based on my understanding of what you are looking to do that is my $0.02.

 

Is that a rod for welding Aluminum? Please help me understand.

 

What color is albr? Does it need A/C or is will DC work? Does it flow
On DC or is it sluggish? Can it braze Al?

 

I just watched a dude on weld.com weld up a old tractor block with ERCuAl-A2 he used AC and he said he likes AC but he didnt mention anything about anything except he likes the AC cleaning action. https://www.youtube.com/watch?v=iyAykUm_Ykg

 

Forget all that crap for now and become profeccient at steel. We be farting with that , been at this 40+ years and have Never used ita d unlikely to tomorrow. Meanwhile made well north of 100000 welds, 1000's of feet on steel.

 

Its more like DC TIG welding on aluminum, but just not that bad.

 

When you're working with Aluminum Bronze (ALB) you need to make certain of your application and the type of ALB you need. A1 is non iron bearing and good for overlay while A2 is iron bearing and is good for overlay as well as build-up and multi pass. So A1 is alloy#610 and A2 is alloy# 618. I've stuck copper to steel with A2. Requires a read up before using in my opinion but it's a fun product to mess with. I enjoy messing with Silicon Bronze as well (SIB) alloy#656. Fun to use. Other fun fillers are Phos-Bronze alloy#521 and Deox-Copper alloy#189. All fun if you want to explore the specialty Tig repair or Artsy world.

 

ERCuAl-A2 (aluminum bronze) and ERCuSi-A (silicon bronze) are both handy to have in my experience.

Silicon bronze can be used on galvanized or where you don't want a really high ultimate tensile strength filler metal.

Aluminum bronze is a good all purpose "stick two things together" rod.

Part of why people like AC with the weld brazing rods is because they're generally very susceptible to contamination. Neither one of them can handle it very well and if the contamination is heavy enough they won't wet down onto the base metal. The cleaning action of AC helps them weld nicer but it's unnecessary if you do a thorough prep job. All AC does is let you be lazier on the prep.

Depending on the repair work being done, you may want to have some high tensile strength low alloy or heat treatable steel filler metal. Things like ER80s-D2 for free machining steels, ER120s for things that need good as welded notch toughness or some of the chrome-moly steel fillers like ER4130 and ER4340 if post weld heat treating is required.

Sometimes it's handy to have nickel rods on hand for welding dissimilar mystery metals. I've used both Inconel 622 and 625 for that kind of repair.

None of those are exactly cheap so I would think about what kind of work you aim to do and try to set your filler metal selection up to support it. Once you have steady income you can worry about expanding the selection. Really the main thing to have for repair work is a wide range of ultimate tensile strength filler metals that are all compatible with mild, low and medium carbon steels. Some repairs it's better to under match the filler, some you want to over match, it's good to have choices on hand to pick from when something doesn't work.

 

I have a related question to this one about TIG brazing. In normal brazing the process is to heat the parent metal to the point where it melts the braze rod. In TIG brazing is the method the same or is simply melting the rod and feeding it into the pool of Al bronze sufficient? On youtube i see tig brazing done by basically heating the braze rod puddle to the point that it melts more braze rod; i don't see the parent metal being hot enough to melt the rod like i see in gas brazing videos.

 

There are two processes that people will call "brazing" but they are technically two different processes. Per the American Welding Society definition:

"Brazing" is a joining process which relies on capillary action to distribute a filler metal that becomes fully molten between 840°F and the solidus temperature of the parent material (the temperature when 100% of a piece of metal is still a solid). This process is typically only done with furnaces, oxy-fuel, induction heaters etc because you need a low density heat source to get the filler to flow and utilize capillary action. If the filler metal is fully molten below 840° F it is termed soldering.

"Braze welding" is a different joining process that uses the same kind of filler metal as "brazing" but the filler is distributed into the joint by deposition, not capillary action. That's why you don't use flux to "braze weld" with TIG, there's no capillary action and so you don't need the braze to flow like you do with an oxy-fuel flame torch. You deposit the filler metal where it needs to be.

TIG/MIG braze welding is identical to TIG/MIG welding except the temperature of the arc is low enough that the parent metal doesn't become fully molten but high enough that the filler metal will.

 

Go to Harris Products Group and look in the Consumables column and you'll find many answers to "brazing" questions

View attachment Screenshot 2023-07-19 190926.JPG

 

Go to Harris Products Group and look in the Consumables column and you'll find many answers to "brazing" questions

Just to confuse the issue, the Harris people are discussion Brazing and I think the OP is more interested in Braze welding.

Jack

 

This has been a great discussion. I love learning. Quite a few people with ton of experience and knowledge here. What is the opinion of traditional gas brazing and tig brazing? This is what my common sense would tell me. Anytime you can tig braze you should. It seems to me with traditional gas brazing you are dumping TONS of heat into the material all in different amounts the further you get away from the repair site. What says Weldingweb.com?

 

What is the opinion of traditional gas brazing and tig brazing? This is what my common sense would tell me. Anytime you can tig braze you should.

I have always gas brazed. I'm not sure if it possible to TIG braze unless it is small scale. Most people that use TIG, braze weld.

It seems to me with traditional gas brazing you are dumping TONS of heat into the material all in different amounts the further you get away from the repair site. What says Weldingweb.com?

It is not "tons of heat", it is sufficient heat. Brazing is done by heating the joint and surrounding area to the brazing temperature and then adding filler to the joint where it is melted by the hot base metal and is drawn into and around the joint by capillary action.

Braze welding is done is the same way as fusion welding except at a lower temperature and there is no fusion of the base metal. The heat input is localised and filler is added as a fillet - one dab at a time.

Jack

 

Perhaps if you tig weld, then tig weld. But tig brazing does not really compare to o/f brazing. With O/f brazing, because of surface area o/f can be extremely strong. O/f is extremely versitile. Acetylene is best to use to control heat input. Great for dissimilar metals too. Variety of fillers for different applications and different flow consistencies.

I tig braze, but have not really figured out a best application. I don’t know enough to trust it for structural applications. It is good for wear resistance, minimize corrosion, and good electrical contact.

 

Lots of people, allot more knowledgeable than me, have already contributed a ton of good information to this thread. It seems to me that there are several heat application processes that are overlapping here, so let me try to group them into categories to perhaps simplify the discussion.
1. Soldering - this is a low temperature process that relies on flux for cleaning action and solder to wet and bond to the materials being soldered. The base material stays intact beyond little etching done by flux.
2. Silver soldering - higher temperature soldering process. Solder includes low percentage of silver to raise its melting point. More aggressive fluxes can be used at higher temperatures.
3. Brazng - Similar to silver soldering, but happens at even higher temperatures above 830 degrees. At these temperatures base metals burn off oxides, hence use of flux is not required. Although some companies label their silver soldering fluxes as brazing fluxes. I think this is where confusion sets in. Some metals like iron either need flux to be used with 800 degree braze rod or be heated to much higher temperature than is required to melt braze rod.
4. Welding - in this process the base metal will melt and form an alloy with filler metal or with other parts molten metal. Most definitions only mandate that base metal must melt for the process to be welding. This is insufficient; base metal must be able to alloy with filler metal or the other parts base metal in the case of fusion welding. If melting was the only requirement; then you could weld steel to aluminum... but you can't.

This is just how i understand the differences in the processes.

 

Brazing and soldering are the same process but performed at different temperatures.

Silver soldering is brazing with a confusing name.

Brazing and Braze welding are not the same.

Most definitions of welding say "coalescence" and the materials may not be metal.

Jack

 

I read the thread, but sadly it didn't answer a couple of questions I have, yet. If brazing or braze welding don't melt the underlying metal, then can it be used to join aluminum to stainless? Or can silver soldering.

 

Short answer is no. Depending on what strength you want to achieve there is a product made my Harris called All Solder 500. It kind of solders most any metal to most any metal. If I remember correctly the tensile is like 25K.

 

Thank you. I only need it to prevent some threads from ever loosening under moderate shock without heat.
That'll work well I think. Threaded 4140, then an aluminum disc, then the "nut" which will be either 4150 or stainless. Disc may wind up being stainless too, but that's not the current plan.

 

Can't use threadlocker or a self-locking nut like a nylok?

 

Hi Dave. I can't for this project. I wish that were an option.

 

If my memory serves me ( I used to work there back in the day ) They had a point of purchase pack available. 3' of solder and a .5 oz flux in a little tube. Goes liquidus at 500 degrees F.
Good Luck.