TY  - JOUR
U1  - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed)
A1  - Strittmatter, Joachim
A1  - Clipa, Victor
A1  - Gheorghita, Viorel
A1  - Gümpel, Paul
T1  - Characterization of NiTi Shape Memory Damping Elements designed for Automotive Safety Systems
JF  - Journal of Materials Engineering and Performance : Special Issue: SMST 2013
N2  - Actuator elements made of NiTi shape memory material are more and more known in industry because of their unique properties. Due to the martensitic phase change, they can revert to their original shape by heating when subjected to an appropriate treatment. This thermal shape memory effect (SME) can show a significant shape change combined with a considerable force. Therefore such elements can be used to solve many technical tasks in the field of actuating elements and mechatronics and will play an increasing role in the next years, especially within the automotive technology, energy management, power, and mechanical engineering as well as medical technology. Beside this thermal SME, these materials also show a mechanical SME, characterized by a superelastic plateau with reversible elongations in the range of 8%. This behavior is based on the building of stress-induced martensite of loaded austenite material at constant temperature and facilitates a lot of applications especially in the medical field. Both SMEs are attended by energy dissipation during the martensitic phase change. This paper describes the first results obtained on different actuator and superelastic NiTi wires concerning their use as damping elements in automotive safety systems. In a first step, the damping behavior of small NiTi wires up to 0.5 mm diameter was examined at testing speeds varying between 0.1 and 50 mm/s upon an adapted tensile testing machine. In order to realize higher testing speeds, a drop impact testing machine was designed, which allows testing speeds up to 4000 mm/s. After introducing this new type of testing machine, the first results of vertical-shock tests of superelastic and electrically activated actuator wires are presented. The characterization of these high dynamic phase change parameters represents the basis for new applications for shape memory damping elements, especially in automotive safety systems.
KW  - Dynamic testing plant
KW  - Dynamic tests
KW  - Ni-Ti wires
KW  - Shape memory alloy
Y1  - 2014
SN  - 1059-9495
SS  - 1059-9495
U6  - https://doi.org/10.1007/s11665-014-1045-1
DO  - https://doi.org/10.1007/s11665-014-1045-1
VL  - 23
IS  - 7
SP  - 2696
EP  - 2703
S1  - 8
PB  - ASM International ; Springer
ER  -