UTILIZATION OF SHAPE MEMORY ALLOY AS A SENSING MATERIAL FOR SMART STRUCTURES

摘要

In developing smart structures, the proper restortion through the detection of internal abnormalities in structures are necessary. In this respect, this study deals with shape memory alloys (SMA) which are selected from intelligent materials. Particularly, studies were carried out on sensing materials to explore such possibilities. The relationship of deformation to electrical resistance was clarified by various tensile tests of SMA wires. Interesting results were obtained such as (1) the SMA wire indicating the possibilities of detecting changes in strain in an extremely broad region, and (2) maximum hysteresis of strain can be estimated from electrical resistance at the time of load removal. Experiments were further carried out on a model of a small-scale structure with attached SMA wire and springs. The results verified the detection of deformation and the control functions.