Materials of active-piston actuators

摘要

The invention concerns an actuator that includes an active piston, an inner sliding cylinder and an outer cylinder in which the said sliding cylinder is pre-stressed, where one of the cylinders is in a material with a negative thermal expansion coefficient or one that is close to zero, with the other cylinder having a positive thermal expansion coefficient, in which the material of the cylinder with negative expansion coefficient or one close to zero is one of the following materials: gamma-ZrMo₂O₈ in cubic structure, Zr₂W P₂O₁₂, a silicious faujasite, Lu₂ (WO₄)₃, ZrW₂O₈ in cubic phase, with nanograins whose size is approximately between 10 nm and 75 nm, or any possible combination of these materials.