Development and Evaluation of Multi-ferroic Actuator/Sensor Materials made by Rapid-solidification Process

指出了多铁性方法在智能/灵巧技术中的技术重要性，指出了基于铁性材料元件间的互耦效应设计先进的多功能执行器/传感器的方法。两种类型的多铁性致动器/传感器装置。即（1）磁驱动复合致动器和（2）MEMS多功能声表面波传感器。首先，大型鲁棒复合材料驱动器是在铁磁金属（Ni）基体中加入超弹性纤维或形状记忆合金（TiNi）层片的复合结构。这种多铁性复合材料可以通过施加无线磁场以高速驱动以及显著增强的应变。其次，介绍了多功能设计的声表面波多铁性传感器。在叉指换能器之间的表面部分上，通过磁控溅射形成环境活性材料膜，例如SMA、FSMA、磁致伸缩合金等。通过对声表面波的幅值和相位变化信号的分析，可以无损地检测各种环境敏感参数，如温度、磁场强度、应力、加载滞后和内部损伤等。因此，这些结果表明，有前途的新型多功能复合驱动器和传感器的基础上的多铁性效应。

Technical importance of multi-ferroic approach for designing advanced multi-functional actuator/sensors based on a mutual coupling effect between ferroic material elements is pointed out for intelligent/smart technology. Two types of multi-ferroic actuator/sensor devices. i.e. (1) magnetically driven composite actuator and (2) multi-functional surface acoustic wave (SAW) sensor by MEMS are presented. First, a large-scale robust composite actuator is the composite structure which is reinforced by the superelastic fiber or lamellar of shape memory alloys (TiNi) in the ferromagnetic metal (Ni) matrix. This multi-ferroic composite can be driven with high speed as well as considerably enhanced strain by applying a wireless magnetic field. Secondarily, multi-functionally designed, multi-ferroic senor device using surface acoustic wave (SAW) is introduced. On the surface part between IDTs, environmentally active material films such as SMA, FSMA, magnetostrictive alloy etc. are formed by magnetron-sputtering. Various environmental sensing parameters i.e. temperature, magnetic field strength, stress, loading hysteresis and internal damage etc. can be evaluated nondestructively from the signal analysis of amplitude and phase change of SAW. Consequently, these results show the promising new types of multi-functional composite actuator and sensor based on multi-ferroic effect.