"Tim Wescott" wrote in message
...
I've always been told that one of the cool things about hypereutectic
aluminum alloy is that its thermal expansion coefficient is significantly
lower than plain ol' aluminum, which makes it a handy material for
pistons. (The other cool thing being that all those silicon particles
can make for a hard, low-wear surface if you machine it correctly).

I was curious yesterday so I went prospecting on Matweb -- it listed
pretty darn near the same expansion rates for 2024 and an alloy with 18%
silicon. It also said the CTE was "derived from similar alloys on
Matweb", which makes me wonder what they mean by "similar". So now I
don't know what to believe.

Anyone know a handy chart of aluminum alloys and their coefficients of
thermal expansion? Google is not my friend in this: when I do a Google
search all I get are enthusiastic articles by gearheads like me. I can
learn all the stuff I already know about the virtues of the stuff, not
any engineering data about those virtues.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com

There is some info on chemical composition and mechanical properties
he http://www.art-piston.com.tw/p-1.html