In many situations, the bolts of a mechanical design are seen as having a secondary importance, when in fact they have fundamental aspects of its operation, once they are used within the loading limits established by the manufacturer [1]. If not, the bolts may have three major types of failure: fracture under high load, self-loosening and untightening. Furthermore, the behavior of SMA components subjected to Transverse Cyclic Shear (TCS) was so far unknown. This type of load can make bolts to self-loosening their preload quickly, depending on the frequency and amplitude of vibration imposed on the joint. Currently, there are some devices that can prevent the loss of preload by TCS but some studies have shown that these devices can be overcome in certain test conditions [2]. In order to solve or minimize these problems associated with bolts, new materials have been studied as, i.e.. Shape Memory Alloys (SMA). Such alloys belong to the class of active materials and have the surprising ability to recover an "apparently plastic" strain upon heating above a critical temperature. In this context, a possible alternative to minimize or even eliminate the mentioned drawbacks would be manufacturing these elements from SMA.
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