Surface preparations and durability of iron-based shape memory alloy adhesively-bonded joints

Abstract

Developing a bonded prestressed solution for strengthening structures utilizing an iron-based shape memory alloy (Fe-SMA), is of significant interest. This study is the first systematic investigation of adhesively-bonded Fe-SMA joints to achieve complete cohesive failure, which is an essential prerequisite for bond integrity. The Fe-SMA surface was prepared by combining UV/ozone exposure (UV), sol–gel (SG), and primers (PC, PNC), and the failure mode of the joint was investigated using the floating-roller peel test. Furthermore, the joint durability was studied through artificial aging using a salt spray cabinet. Cohesive failure was obtained for all investigated adhesives, and the effect of every surface preparation step was described. The application of sol–gel was found to be a crucial step in obtaining complete adhesive failure.