A variable temperature,tensile testing cryostat

This paper describes a gas spray cryostat for tensile tests, which can also be used with testing instruments where both the crosshead on the top and the hydraulic piston on the bottom are moving simultaneously. A twin tube is used for the heat exchanger together with a ‘Thermocoax’ heater. This provides a short cooling and heating time during temperature change tests. The connexion between sample and load cell is frictionless, without the commonly used seals, and therefore very small forces can be resolved. In order to avoid unwanted deformation of the specimen due to the thermal expansion of the connexion rod, the specimen length is measured and controlled directly.