Coefficients of thermal expansion over different temp ranges
Coefficients of thermal expansion over different temp ranges
(OP)
I have found a reference which defines the coefficient of thermal expansion for a gray iron over several different ranges. The puzzler is why they all begin at ambient temp. Ex. 68-212° is 5.6 and 68-392° is 5.9. How can this be? What if the final temp falls in both ranges (195°) then you get two answers for the same equation.





RE: Coefficients of thermal expansion over different temp ranges
corus
RE: Coefficients of thermal expansion over different temp ranges
That coefficient is a function of temperature so if you want the expansion over any range you must get a curve of L vs T where L is the length of the specimen; the coefficient at any temperature would be
delta L/(L*delta T)
This would be the average over the range delta T. If delta T were very samll, then in the limit it would be the coefficient at that T.
RE: Coefficients of thermal expansion over different temp ranges
When you run across a set values as you have you should take the range that is the closest to you temperature requirements.