Figure 7. Eigenvalues of full-span sample, illustrating the hysteric, nonlinear response with a temperature sweep. Results shown for second bend (a) through fifth bend (d)

From

Active Stiffness Method for High Cycle Fatigue Mitigation using Topical Thin Foil Shape Memory Alloy

Nicholas G. Garafolo, Rachel Collard

Journal of Mechanical Design and Vibration. 2017, 5(1), 11-20 doi:10.12691/jmdv-5-1-2