Stainless steel valves

[masmith]

At 11:58 AM 3/21/96 +1100, you wrote:

>> The best currently used valve material is "Inconel", once
>>used in Bell's X-15 aircraft (or rocket?)
<snip>
>Inconel is actually a brand name for a range of Nickel based 'super alloys'
>(eg Inconel 718), but there are also iron and cobalt based super alloys
>(examples being Incoloy 800 and Stellite 6B respectively).   1200C is right
>at the upper limit for the conventional super alloys and at these
>temperatures no significant load could be carried.  Generally, 950C is
>regarded as the upper limit for load carrying applications. 

the Space Shuttlle Main Engine is about 80% Inconel alloys.

I am not sure if Hydrogen embrittlement is a problem with any of you
(does anyone do Hydrogen injection) but you have to watch out for it with
inconels.
(i am honestly not sure if it's only a cryogenic or high temp problem
metallurgy is not my expertise)
Matt Smith
masmith089 at qnet.com
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