PSI - Issue 64

Ali Saeedi et al. / Procedia Structural Integrity 64 (2024) 2044–2050 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 4. Temperature distribution in the cross section view for activation voltage of a)8V, b)10V and c)12V

3.3. Effect of reinforcement size In the subsequent analysis, the dimensions of the reinforcement were changed while maintaining a constant voltage level to evaluate the impact of reinforcement size on temperature distribution. Fig. 5, displays the time-temperature diagrams for bar and strip SMA wires. The dimensions of the reinforcements were chosen such that the cross-sectional areas are equivalent for each case. For the strip reinforcement, the width was consistently set at 15 mm, while variations were made in the thickness, as illustrated in Fig. 5. For the bar, the variable parameter was the radius of the reinforcement.

Fig. 5. Time-temperature diagram for the Fe-SMA strip (left) and bar (right) with different dimensions

The results indicate that increasing the thickness of the strip from 2 mm to 10 mm (a five-time increase in cross sectional area) results in a 56% increase in maximum temperature. Conversely, for the bar, increasing the diameter from 3.1 mm to 7 mm, which also represents a five-time increase in cross-sectional area, leads to only a 23% rise in maximum temperature. This discrepancy highlights that strips are significantly more sensitive to changes in size. The temperature distribution for different sizes of the reinforcement, measured 30 seconds after activation, is depicted in Fig. 6.