Thermal extensometer

Abstract

The device employs an electrical transducer for measuring thermal deformation in a specimen with a high degree of resolution. The device basically comprises a link which linearly spans the specimen in the direction and at the location in which the deformation is to be measured, and a displacement sensor with a broad temperature range such as a capacitance-based linear displacement sensor. The link is fixed to the specimen at one end and free at the other end. The link is constructed with negligible thermal expansion such as by selecting a material for the link that has a very low thermal coefficient of expansion. In one embodiment the link is constructed in two different length sections each having a different thermal expansion coefficient with the sections extending in opposite directions to provide an effective or resultant expansion that is negligible with temperature change. In another embodiment part of the sensor is supported by a frame having a higher thermal expansion coefficient than the coefficient of the link which is a single section link.

Dependencies are inferred from the claim text.