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Does bronze rust?
aerosam - 26/2/09 at 06:09 PM

I was thinking of coating my front wishbones lightly with bronze (10%Aluminium - 88% Copper - 2%iron)and polishing them up (don't ask how - it's complicated) but the coating would be thin and polished up it should look quite nice.

Just wondering if it would tarnish/corrode over time.


liam.mccaffrey - 26/2/09 at 06:11 PM

bronze can corrode but probably not in this environment. It will probably dull though


Alan B - 26/2/09 at 06:23 PM

Strange alloy....I thought bronze was a copper/tin alloy? Must be more of an Ali/bronze I'm guessing?

[Edited on 26/2/09 by Alan B]


BenB - 26/2/09 at 06:34 PM

Bronze doesn't corrode but it goes pretty dark with time. Brass goes more orangey gold with time. Copper develops verdigris....


liam.mccaffrey - 26/2/09 at 06:54 PM

quote:
Originally posted by BenB
Bronze doesn't corrode but it goes pretty dark with time. Brass goes more orangey gold with time. Copper develops verdigris....


I believe brass can suffer from stress corrosion cracking


Hellfire - 26/2/09 at 07:00 PM

Bronze does corrode - it turns into into a kind of "Bronze Oxide" known as a Patina.

When the Patina forms it has an iridescent look of a bluey/green type colour (from the copper/tin mix).

Putting iron into is will cause rusting - why put iron in?

Steve


ReMan - 26/2/09 at 07:05 PM

I thought you could only plate with elements?
That's a personal thought not a fact


James - 26/2/09 at 07:18 PM

Is there not a disadvantage in this similar to chroming... the wishbone can crack and the cracks be hidden under the chrome.

Then you don't know there's a problem until the wishbone falls in 2!

Cheers,
James


ReMan - 26/2/09 at 07:21 PM

quote:
Originally posted by James
Is there not a disadvantage in this similar to chroming... the wishbone can crack and the cracks be hidden under the chrome.

Then you don't know there's a problem until the wishbone falls in 2!

Cheers,
James


Woul 't that be more risk with paint? Plating is only microns thick?


James - 26/2/09 at 07:29 PM

quote:
Originally posted by ReMan
quote:
Originally posted by James
Is there not a disadvantage in this similar to chroming... the wishbone can crack and the cracks be hidden under the chrome.

Then you don't know there's a problem until the wishbone falls in 2!

Cheers,
James


Woul 't that be more risk with paint? Plating is only microns thick?



Yeah, maybe. It was something I was told, that's all!

EDIT: actually, it was something discussed on here IIRC.

[Edited on 26/2/09 by James]


aerosam - 26/2/09 at 08:01 PM

quote:
Originally posted by ReMan
I thought you could only plate with elements?
That's a personal thought not a fact


It's not plating, it's electric arc thermal spraying with pre-alloyed wire, like i said, it's complicated.

I'm going to see what happens by spraying up a couple of spare pieces of tube, laving one outside and one in the garage and see what happens to them.


aerosam - 26/2/09 at 08:07 PM

quote:
Originally posted by Alan B
Strange alloy....I thought bronze was a copper/tin alloy? Must be more of an Ali/bronze I'm guessing?

[Edited on 26/2/09 by Alan B]


That's how it is supplied as a wire, usually used to re-coat bearing race surfaces


handyandy - 26/2/09 at 08:23 PM

may i ask a question thats slightly related to this thread.....
i was thinking of having the wish bones nickel plated ( don,t know the elements), for two reasons, will rarely need polishing & looks nicer than chrome (imo).
parts of my race bike are nickel plated & looks good, alot easier than having to keep polishing to keep the part looking good.

question is, would this weaken the wishbones at all ?

cheers
andy


ReMan - 26/2/09 at 08:24 PM

quote:
Originally posted by aerosam
quote:
Originally posted by ReMan
I thought you could only plate with elements?
That's a personal thought not a fact


It's not plating, it's electric arc thermal spraying with pre-alloyed wire, like i said, it's complicated.



Of course it is, I should have known!


britishtrident - 26/2/09 at 08:35 PM

Bronze spraying shouldn't cause any embrittlement.

Likewise Nickle plating is usually regarded as acceptable.


Simon - 26/2/09 at 08:38 PM

Bronze oxidises (like ally, in that the outer "rust" layer is quite impenetrable by elements once formed), depending on environment will go very dark in polluted towns (see most sculptures in London) and green (verdigris) by the sea (like good olf copper roofs).

See this which we did about 5 years ago



If you polish it, be prepared to keep polishing it, as even a fingerprint will leave a mark that will need polishing out.

We do stuff for Clive Barker, see



ATB

Simon

[Edited on 26/2/09 by Simon]


Hellfire - 26/2/09 at 09:21 PM

quote:
Originally posted by ReMan
I thought you could only plate with elements?
That's a personal thought not a fact


I was up in Leeds today advising on different coatings - there are loads!

Titanium, Aluminium Nitride, Titanium Aluminium Nitride, Aluminium Titanium Chromium (which is a very blue to yellow burn characteristic pattern) some are awesome!!!

Trouble is it costs a fortune as temperatures of above 900C are involved.

Steve


flak monkey - 26/2/09 at 09:55 PM

We have a metal spray shop at work which is used for building up shafts. Its not a complicated process but has its disadvantages.

I assume you are talking about PVD/CVD coatings Steve. Some of the coatings are incredible and very hard. Its how the coatings are applied to carbide, ceramic and CBN tips for those not in the know

David


aerosam - 27/2/09 at 06:42 AM

sounds cool flak monkey. The processes I use are plasma spray, arc-wire spray and HVOF spray.

We spray a huge range of coatings, alloys, carbides, ceramics (aka thermal barrier coatings - good for over 1500 deg C!).

Our work is all engineering, not as pretty as simons stuff, most of ours is dimensional restoration and get's machined after spraying.

I'll have a go with some spare steel next week and post some pics up.