Free Layer Blade Damper By Magneto-mechanical Coating

To prevent blade failure, the excited resonant response needs to be attenuated to an acceptable level. Several investigators have presented approaches to suppress blade vibration by providing additional damping through blade dampers. Among them, a surface high-damping magneto-mechanical coating layer, so-called free layer damper developed by the PI, is likely to be more practical. The proposed Phase I efforts include: (1) characterization and identification of magneto-mechanical coating stress/strain dependent nature associated with the damping mechanism at various temperature levels (room-1500 F), (2) development of a vibration testing procedure to characterize the dynamic properties of uncoated and coated beams at various temperature levels (room-1500F), (3) a framework will be developed for the estimation of the effect of static mean stress on damping properties of the coating, and (4) developing an analytical approach for predicting the dynamic performance and the nonlinear behavior of the beams and blades coated with a thin layer coating with thickness < 0.005 inch. In Phase I option, assessment of total fatigue life of the coating materials under bending condition will be conducted. In addition, the corrosion of the coating material will be examined thoroughly. Finally, a new nanotechnology will be developed to systematically organize and manipulate stress-induced irreversible movement of the coating magnetic atom domain walls to achieve high damping and damage resistance.