At 06:15 AM 7/19/06 -0500, John Thompson wrote:
>Using brass requires higher temperature and thereby negates the
>advantage of the heat treatment. Use brass and all you have is a
>light-gauge 531 set.
Did the higher temperature anneal the 753 or over-harden it, thus making it brittle at the joint? I had always presumed the latter. There are 3 ways to heat treat (harden to increase UTS) alloy steel without also using chemicals:
1. Heat and water quench 2. Heat and oil quench 3. Heat and allow to cool in still air (for air hardening alloys)
These methods are for different steels. The third method is used where no distortion of the work can be tolerated, which can happen if it is quenched. My guess is that 753 was an early air hardened alloy that could not be reliably re-heated to brazing temperature and air-cooled without compromising its strength one way or another. I'm thinking the new steels Reynolds now has are air hardened at a higher temperature and safe for brazing or TIG welding. This is just based on my engineering and machine shop experience. If anybody has inside information from Reynolds, please jump in and correct me.
John Betmanis <johnb@oxford.net>
Woodstock, ON Canada