In the study presented, the damping capacity of shape memory alloys in theaustenitic range was considered. The investigations on the dynamicbehaviour of pseudoelastic shape memory alloys start with tensile tests onNiTi specimens at frequencies of up to 4Hz. These experiments show that thebeginning of the transformation process is more difficult to observe andthat the critical stress value for the transition to martensite becomesobviously smaller at higher strain rates. Furthermore, the area of thehysteresis loop is reduced with increasing strain rate. The dampingbehaviours of NiTi and steel are directly compared in experiments on apre-strained string. The system is excited by hammer impact as well as by anelectrodynamic shaker. It is pointed out that the damping capacity is highlydependent on the vibration amplitude. Further experiments are performed withcoil springs made from NiTi and steel. A stiff beam on which additionalmasses are mounted is supported by two coil springs so that the wholeassembly can be considered as a spring-mass system. The results which wereobtained in the string experiments are verified by these investigations.
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