The effect of surface texturing on thin film reversible adhesive bond strength

Adhesives with reversible bonding characteristics are useful in different applications which demand assembly and disassembly of components, over repeated times. To achieve reversible bonding, the bonding strength of the adhesives on the substrate should be sufficiently high to ensure cohesive failure and with minimized adhesive failure after each bond/debond cycle. This study aims at investigating the bonding strength of an aromatic thermosetting copolyester (ATSP) adhesive deposited on aluminum substrates prepared with conventional sandblasting technique, and laser surface texturing. The deposited ATSP coating was bonded at a temperature of 340 °C and debonded at various temperatures from 25 to 200 °C using a bond strength tester. The reversibility of the coating was shown through multiple bond/debond cycles. The experimental findings revealed significant improvement of bond strength through laser surface texturing, compared to sandblasting by more than 27–63% for debonding at temperatures from 25 to 200 °C. Failure analysis of the coatings showed the predominance of adhesive and cohesive failure for sandblasted and laser textured substrates, respectively. The role of surface topography parameters was investigated for each substrate preparation method, and correlated to the bond/debond experiments.