Does Brass Shrink at Very low Temperatures?

Most recent answer: 06/10/2010

Q:
Hi - does brass shrink when subjected to very low temperatures such as -196 celsius. If the brass shape was circular e.g. a ring or washer would the ring split? Look forward to your answer
- Colin Freeman
England
A:
Yes it does.  The standard linear expansion coefficient for brass is about 19x10-6 per degree C.  To go from room temperature, 20oC to the temperature of liquid nitrogen, -196oC you would get an shrinkage factor of about 0.4 percent.  Perhaps my pal MikeW knows if the linear expansion is valid at those temperatures.  (Beats me. /mbw) In any case, a brass ring would not split.  Everything contracts proportionally so no internal forces are generated.  Consider a shrinking rectangular sheet of brass.  If you cooled it down, it would not split.   Now think of drawing some imaginary circles outlining the ring before and after.  No problem, no split.

LeeH

(published on 06/10/2010)