Cryogenic Fluid Transfer Components Using Single Crystal Piezoelectric Actuators

Cryogenic fluid transfer components using single crystal piezoelectric actuators are proposed to enable low thermal mass, minimal heat leak, low power consumption and fast response for cryogenic fluid transfer and handling systems to support NASA Lunar Lander, Ground Operations, Ares, and Lunar Surface Systems programs. Single crystal piezoelectrics are attractive because they exhibit 3 to 5 times the strain as conventional piezoelectric ceramics, have very low strain hysteresis, and retain excellent piezoelectric performance at cryogenic temperatures. Single crystal piezoelectric actuators including flextensional actuators and piezomotors were developed in Phase I and incorporated into cryogenic valves. The prototyped piezoelectric cryogenic valves were tested showing excellent flow control performance at temperature ranged from room temperature to liquid nitrogen temperature and pressure ranged from 50 psi to 3000 psi. In Phase II PMN-PT single crystal flextensional actuators and piezomotors design, fabrication and integration into cryogenic valves will be optimized, reliability of these piezoelectric cryogenic valves and actuators will be investigated. These advanced cryogenic actuators also hold promise for shape, motion and force controls in NASA, DOD and industrial applications.