On Sat, 19 Jan 2008 09:03:46 -0800, Jon Anderson wrote:
I am working on product that is comprised of aluminum sleeves affixed to
carbon fiber tubes with structural adhesives. We have tensile tests that
show we have more than enough strength for normal use. However, I am
looking at the 200 degree service limit for the adhesive and wondering
just how hot this part might get say, sitting in the sun out in Phoenix
in the middle of summer.....
It's winter here in Calif. so hard to collect data. I might ship some
parts off to a friend in OZ to collect data as it's summer there. But
thought I'd ask if anyone here might have done any testing of this
nature and know.
I have approx 3/4"dia by 2" long aluminum, bonded to 1/2" carbon fiber.
This resides near an engine, so worst case would likely be a hard run
through the desert, then being parked with this part in direct sunlight
while taking in heat from the engine.
Once I have an good idea what temps we might see, I can specify in the
next tensile test that the parts be heated to this temp before being
pulled.
Thanks,
Jon
200F or 200C? One inch away from the engine or one foot?
My gut feel is that if it is more than four inches away from the top end
of the engine, or more than 10 inches away from the exhaust it'll get
"ouch" hot but not "sizzle" hot. For most people, "ouch" hot is about
50C (so about 120F). "Sizzle" hot can be taken as a bit above boiling,
or 110C (230F) (I wonder just what "sizzle" hot really is...).
If the critical temperature is 200F you should probably stop now -- it'll
fail often enough in service to make you look bad, even if it usually
works fine. If the critical temperature is 200C, you're probably fine --
but I'm not a mechanical engineer, so don't go quoting _me_ on that!
--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com
Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes,
http://www.wescottdesign.com/actfes/actfes.html