Re: [ATM] bending brass

[Mitch_Bisnauth@Cknainc.com]

If i remember my ingeneering/metalurgy correctly the hardening process 
(heating and 'rapid' cooling) for iron containg carbon was because the 
process allows the carbon to dissolve/migrate into the iron structure and 
form all sorts of fancy things then the 'rapid' cooling constrains the 
carbon in solution yielding a matix that has the "carbide" in various 
crystalline forms....i don't recall any such posible mechanism with brass 
simply because there is no carbon or other element to form a relatively 
rigid bond with the copper....the other alloying elements are merely 
sitting in the crystal structure blocking dislocation movement....on the 
other hand I can't remember the copper/tin copper/zinc eutectic 
diagrams...  (i could be hopelessly wrong..:-)..) 

MitchB



"Bob May" <rmay@nethere.com> 
Sent by: atm-bounces@atmlist.net
05/02/2008 06:34 PM

To
<atm@atmlist.net>
cc

Subject
Re: [ATM] bending brass






I don't recall any need to quench or cool slowly for brass or
other copper alloys of the general nature.  I've always found
that brass turns much softer if you heat it to a dull red.
Letting it cool naturally or quenching it really didn't matter.
It also didn't seem to matter how long I kept it hot, just
getting the color and letting it go was enough.
Quite supprisingly, my Machinery's Handbook doesn't seem to go
into the annealing and hardening process of copper alloys.
I'll also note that the copper alloys all "work harden" which
means that as you bend them, they get harder and more brittle.
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net

----- Original Message -----
From: Richard <cnc@cncservo.co.uk>
To: Gil McFarlane <atm@atmlist.net>
Sent: Friday, May 02, 2008 7:52 AM
Subject: Re: [ATM] bending brass


> Hi Gil,
>
> Friday, May 2, 2008, 3:06:07 PM, you wrote:
>
> GM> I recall that heating the brass and letting it cool will
make it
> GM> more malleable (is this correct?)
>
> No, it's the other way round for Copper alloys compared to
Steel.
>
> Copper Alloys :
> To Anneal, heat to dull red , hold for 1 hour per inch
thickness, and quench.
> To Harden, heat to dull red , hold for 1 hour per inch
thickness, and cool slowly.
>
> Steel Alloys :
> To Anneal, heat to bright red, hold for 1 hour per inch
thickness, and
> cool very slowly.
> To Harden, heat to bright red, hold for one hour per inch
thickness
> and quench in water, brine or oil, depending on grade. Temper
while
> still warm or it will be dangerously brittle.
>
> --
>
> Best regards,
>   Richard in the UK
>
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
>

_______________________________________________
ATM mailing list http://www.atmlist.net/

_______________________________________________
ATM mailing list http://www.atmlist.net/