Gas/Liquid Phase Change Actuator for Use in Extreme Temperature Environments

Manipulating materials exposed to extreme temperature environments presents numerous significant challenges. For example, steel industries require new methods for the direct handling of materials at temperatures greater than 1000°C, and material scientists require new methods for handling specimens at the helium temperature, where high-quality analysis must be performed with very low levels of thermal noise. However, conventional actuators do not work in such environments because of their low thermostability and, more importantly, the loss of the magnetic and piezoelectric properties of the actuator materials. For example, it is well known that magnetism and piezoelectricity completely disappear at temperatures exceeding the Curie point. This paper proposes a new working principle for actuators based on the gas/liquid phase change of working fluids. We show possibilities for the actuator design, including selections for temperature-resistant materials and working fluids at various temperatures. In addition, we discuss the design of the first prototype actuator, which worked successfully at 180°C by utilizing the gas/liquid phase change of water. The basic experimental results show significant potential for the actuator.