Apparatus for measuring the thermal expansion of solids between 1.5 and 380K

Describes a device for measuring the thermal expansion of solids in the temperature range from 1.5 to 380K, based on a three-terminal capacitor method. The construction of the expansion cell allows a fast mounting of the sample without dismantling of the cell, the sample shape being unimportant. The relative sensitivity is Delta l/l=10 -10 for l=10 mm. The systematic error is in the order of 10 -7 . The thermal expansion coefficient can be determined with a sensitivity of 10 -9 K -1 and an accuracy of +or-2%.