Brazing 5083 Aluminium

[murphenzo]

I understand that brazability of 5083 aluminium is classed as low, however I haven't been able to find any information on what actually happens if you do try to braze it?
Is there a process where you can get a sound brazed joint between say 6061 and 5083?

Any help is appreciated.

Justin

 

[TugboatEng]

I think most alloys can be nickel plated and then brazed with a silver/cadmium alloy. What is your intention here?

 

Certainly it's not something one can do at home.
ASM Vol. 6 Welding Handbook should give you some guidance.
You might consider adhesive bonding.


"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[Compositepro]

I know that zinc brazing rods are sold for brazing aluminum at home. I do not know the mechanical properties or if zinc can tell a difference between 6061 and 5083. I've seen holes in aluminum cans sealed as a demo.

https://www.youtube.com/watch?v=wy1dNqXfUws

 

Anything can be done on YT. In the Realosphere, not so much.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[murphenzo]

Hi team. Sorry for the super late follow up. This somehow got lost in the real word continuum of craziness.

I own an aluminium sailing catamaran that's made out of 5083. I was looking for options to repair or modify, without the need to weld, so brazing was looking like a possibility. However it seems that's a no go with 5083 and the more I think about the practicalities of it, it's obvious that it wouldn't be a good option anyway.

Thank you all for the input!

 

[TugboatEng]

What equipment to you have? What is the nature of the job? I spend a lot of time identifying ways to do things without hot work. It's very expensive to get the hot work permit on commercial boats.

 

[murphenzo]

It's a private boat, so no permits required in this case.
I suppose there are two primary applications:
1. Minor modifications, eg attaching brackets for shelves or holding equipment
2. Major repairs in remote places, lets say if I hit (or we get hit by) any object that puts a hole in one of the hulls

My boat is quite weight sensitive, so heavy welders aren't a great option for carrying onboard. I was looking at the brazing option because the gear is small and light and has no risk to electrical equipment on the boat or potential electrolysis issues (if you're powering from shore power). But I think for most places on the boat, the amount of heat that will need to be put in would be a major fire risk, or at a minimum cause damage else where.

Maybe bonding is the way to go for these applications.

 

[TugboatEng]

Yes, bonding is absolutely the way to go. Click Bond has a wide selection of adhesive mount fasteners, mounts, routing clamps etc... They cater to aerospace so order wisely as there is quite a range of pricing on "similar" products.


Belzona has many examples of plate bonding systems for repairing larger holes and such. Again, you'll pay a premium for these products. For less critical applications I'll often substitute acrylic adhesives from manufactures like 3M.

 

[murphenzo]

Thank you for the advice TugboatEng. I will check them out.

 

[EdStainless]

With most metals (Al included) there are special primers for adhesive bonding. These etch the surface slightly and increase chemical activity to achieve better bonding. Find an adhesive that is specifically for Al or one that has a special Al primer.

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P.E. Metallurgy, consulting work welcomed

 

It's a private boat, so no permits required in this case.

If your private boat is operated on public waterways it ceases being private, and you have some legal obligations.
And the laws of physics and of Darwin apply universally.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[murphenzo]

Appreciate the advice on primers. I'll check them out.

Cheers