The Armour Archive

On the Penny washer thread (viewtopic.php?f=1&t=164829) someone posted the following chart.

On that chart, it lists something called aluminum bronze. I have never heard of such a material and would like to know more.

What can the hive mind tell me about it?

I have not really worked with the stuff but what application do you need it for?
Ampcometal.com is one of the big manufactures that comes up when searching google.
From my searching it looks like the alloy is used primarily for non sparking tools for mining, gas, and chemical industry as well as vales and plumbing fixtures.

For the most part this tells us that it should machine well and be a little costly.

It's a combination of copper and aluminum, as opposed to copper and tin (bronze) or copper and zinc (brass.) As with the other two, additional metals might be tossed in to improve its characteristics for different functions.

Applications

Aluminium bronzes are most commonly used in applications where their resistance to corrosion makes them preferable to other engineering materials. These applications include plain bearings and landing gear components on aircraft, engine components (especially for seagoing ships), underwater fastenings in naval architecture, and ship propellers. Aluminum bronze is also used to fulfill the ATEX directive for Zones 1, 2, 21, and 22. The attractive gold-toned coloration of aluminium bronzes has also led to their use in jewelry.

Aluminium bronzes are in the highest demand from the following industries and areas:

General sea water-related service
Water supply
Oil and petrochemical industries (i.e. tools for use in non-sparking environments)
Specialized anti-corrosive applications
Certain structural retrofit building applications

Aluminium bronze can be welded using the MIG welding technique with an aluminium bronze core and pure argon gas.

Aluminium bronze is used to replace gold for the casting of dental crowns. The alloys used are chemically inert and have the appearance of gold.

Alloys similar to aluminium bronze are used in making coins, for example the one and two dollar coins of Australian and New Zealand currency produced by the Royal Australian Mint, some Mexican coins and the Nordic gold used for some Euro coins. The Canadian 2 dollar coin, produced by the Royal Canadian Mint and circulated since 1996, is a bi-metallic piece with an outer ring of nickel-plated steel and an inner circle of aluminum bronze composed of 92% copper, 6% aluminum, and 2% nickel.

I don't need any. I was just curious.

I looked it up on wiki, but that is about all I know.

I have come across it, from time to time, in a maritime context. Never tried any of it, since I never found any in a "scrap" condition. (No sense wasting a perfectly good cleat!)

Many of the home machinist types find it harder to machine aluminum bronze than the normal tin bronzes. Mostly they use it for bearings.

Back around 1997 or so a welding instructor at the local tech school gave me a pallet of welding wire (probably 3 to 4 hundred pounds of wire) that had been donated to them by a local ship yard. There was a lot of stainless; a bit of bronze, inconel, and aluminum; and a roll of slightly darker looking bronze that I later found out was a bronze/aluminum alloy.

I made this mail byrnie out of what I had of the stuff:
http://mailmaker.tripod.com/armor/brnz01.jpg

Warning, mail geekery ahead...
I found it to be a pain to work with compared to other bronze or brass wire I had used for mail. It left a nasty smell on my hands after working with it for a few hours. It was also uncooperative with my usual "score & break" method for cutting rings - where with other wire use my cutters to score a little nick where I want the cut to be, then twist the ring from the end of the coil and it breaks cleanly off... with the bronze/aluminum the scoring would either not be deep enough, or my wire cutters would score it just slightly, then munch right through leaving a jagged/broken looking cut. I was able to adapt my cutting method to something that produced results I was happy with, but I can see how it could be hard to machine as well.

Aluminium bronze is what the 'gold' coins are made out of in my part of the world. It is a hard wearing gold coloured metal mostly used commercially for marine bearings.

Aluminium bronze is what the 'gold' coins are made out of in my part of the world. It is a hard wearing gold coloured metal mostly used commercially for marine bearings.