What is Easton EA70?

[FluffyChicken]

Re:

It should be mentioned Easton didn't make the Aluminium Alloy, they just made the tubes iirc.
It was probably Alcoa who actually made the metal or some other Aluminium alloy manufacturer.

 

[IanS62]

No, it's almost certainly made by Alcoa or Alcan to their specification, much in the same way that Reynolds had their steel tubing made by local companies.

Incidentally, I did some research lately while writing an assignment on metallurgy and found out that Reynolds 531 and 753 were identical alloys (steel alloyed with managanese, molybdenum and chrome in the ratio of 5:3:1, hence the name). It was only the wall thickness and post-extrusion heat treatment that made it different. Reynolds kept that quiet...

I'm available for children's parties, btw

 

[Rampage]

Alcoa are about as good as Easton at answering emails!

 

[IanS62]

I guess they see it as a trade secret, dunno why. What exactly is it you want to know?

 

[The History Man]

No, it's almost certainly made by Alcoa or Alcan to their specification, much in the same way that Reynolds had their steel tubing made by local companies.

Incidentally, I did some research lately while writing an assignment on metallurgy and found out that Reynolds 531 and 753 were identical alloys (steel alloyed with managanese, molybdenum and chrome in the ratio of 5:3:1, hence the name). It was only the wall thickness and post-extrusion heat treatment that made it different. Reynolds kept that quiet...

I'm available for children's parties, btw

That's a little gem of a factoid!

 

[Rampage]

It's to do with how it will anodise.

 

[IanS62]

Ooh, good question. I don't know, I'm afraid. I can ask around for you - I'm in aircraft maintenance and we tend to use aluminium quite a lot. The composition will be as I said, alu with zinc as the main alloy and I can't think offhand of a reason why you can't anodize a zinc alloy, but the heat treatment will be the key. Are you looking at anodise a frame, or components?

Edit; quick phone call. EA70 either 7050 or 7075. The heat treatment is T74, which is "Solution heat treated and then artificially overaged in order to achieve the best stress corrosion resistance. and exfoliation corrosion resistance", which is just what you need on a bicycle frame.

Right, more research. From http://aluminium.matter.org.uk/aluselec ... rowse.asp; if it's a T7 heat treatment then bright anodising and colour anodising are listed as 'not recommended'. Hard and protective anodising yes, but not colour. I'll ask the oracle at work tomorrow (Brian) but I'm fairly sure that's all correct. HTH.

 

[Rampage]

It's a seatpost.
That's a good website, pity it won't work on my ipad!
Thanks,