Annealled brass

I was fabricating a water test pump out of bits of scrap brass and every part was locked together with threads and dowels.

It was then silver soldered together unfortunately it got dropped and bent the inlet to the ram bore.

That was corrected when cool by a steel plug being inserted and light tapping with a small hammer.

There is a bronze guide bush goes in the damaged end so it was repairable.

My question is after the brass has been annealed by silver soldering in time will it go back to the hard state it was before being annealed?

Paul

Edited By Windy on 26/03/2013 10:03:35

Edited By Windy on 26/03/2013 10:04:38

I would say no it won't - unless you work harden it by dropping it repeatedly on to a hard concrete floor or hitting it with a hammer! Some aluminium alloys age harden, but not high zinc (or leaded) brass (which I expect yours will be - CZ121 Pb3 is a very common bar alloy) to any significant extent.

It's a bummer when you scrap a job by dropping it, though - we've most of us been there!

My experience of sheet brass (which is probably a different, harder grade) is that it hardens noticeably overnight.

Neil

A Google search on "age hardening of brass" threw up two previous discussions of this subject on this very site, I suggest you look for them. Both seemed to suggest that many grades of brass do age harden but some high-zinc grades might not. Never studied it myself, but I know copper age hardens, quite quickly too.

David

For a steam boiler, copper and brass will undergo a rapid hardening upon pressure test and later use. Old bits of brased brass parts reharden spontanously in my scrap bin (much less "drill bit snatching" after "a while" , I can't be more precise. Old brass music instruments also, up to the point of crevices on the thinnest parts.

Zephyrin

A brass wind instrument is also subject to intense vibration whilst being played

Roy ( ex bass trombone for over 40 years)