A PARAMETRIC STUDY ON THE FAILURE OF BONDED SINGLE-LAP JOINTS OF GFRE COMPOSITE AND ALUMINUM

This paper investigates the effect of bonding pressure, overlap length and adherent thickness on
the strength and failure load of the single-lap joints of dissimilar materials (GFRE composite and
aluminum). Eighteen groups of joints made of glass fiber epoxy composite laminates and Al have
been manufactured. The stacking sequences [0/±45/90] and [0/±45/90]s were used to manufacture
2 mm and 4 mm thick GFRE composite laminates, whereas Al thickness was 1.5mm and 3mm. In
all cases, the CY219 adhesive thickness was 0.12 ±0.02 mm, and the specimen width was 25mm.
Besides, various values of bonding pressure [1, 2, 3, 4, 5, 6 atm.] were applied.
The experimental results show that, the failure load and strength of the joint increase with bonding
pressure up to 4 atm. Higher bonding pressures do not considerably affect the failure load and
strength. Hence, a bonding pressure of 4 atm. was found suitable for bonding composite to
aluminum. Moreover, the failure load increased and the bonding strength decreased with
increasing the overlap length. However, the increase of failure loads slightly at overlap lengths
larger than 30 mm. Also, increasing the adherent thickness resulted in an increase of the failure
load. Finally, the failure mode of tested joints was composite delaminating