Experimental investigation on debonding behavior of Fe-SMA-to-steel joints

This work is the first systematic study on static behavior of adhesively-bonded Fe-SMA-to-steel joints in applications adopting iron-based Shape Memory Alloys (SMAs). In order to provide a better understanding mechanical adhesively bonded joint, an experimental campaign was established, involving 24 lap-shear tests displacement-controlled loading regime. The test series includes two types Fe-SMAs (non-prestrained and prestrained), three adhesives (SikaDur 30, Araldite 2015, SikaPower 1277), different thickness values (0.5, 1, 2 mm) for adhesive. A digital image correlation (DIC) technique employed measure full-field displacement strain, which were then used infer shear behavior. analyzed basis experimentally derived load–displacement curves, stress profiles along bond line, bond–slip curves; stages observed during process joint: (i) linear stage, (ii) damage accumulation (iii) debonding propagation stage. results indicate that more ductile adhesive or thicker layer possess higher fracture energy, leading greater capacity. also compared against those from carbon fiber reinforced polymer (CFRP) joints. It found Fe-SMA CFRP behave similarly when utilized; nonlinear adhesive, however, significant differences between joints, merit individual analysis.