Joint Strength Optimization of Single-Lap Al 5052-H36 Adhesively Bonded for Off-Road Vehicle Chassis Components

The main objective of this paper is to study the effect of the key parameters on the mechanical strength of adhesively bonded Al 5052-H36 joints. The key parameters are adhesive type, curing temperature, and geometrical parameters. To evaluate the effect of these parameters on the performance of bonded joints, single lap joints (SLJ) coupons were prepared and tested under tension. The adhesives 852/25 GB and Ep 5089 were studied to analyze the effect of the polymer type on the mechanical behavior of bonded joints. The effect of geometrical parameters and curing temperature of adhesive were investigated for joints assembled with 852/25 GB. The distribution of stresses within the bond area was assessed numerically using a linear model and validated with an analytical model. 852/25 GB makes weaker joints and shows cohesive failure, while EP 5089 adhesive resulted in stronger joints and interface failure. Samples exposed to heating cycles generated the strongest joints compared to those cured @ RT and 35 °C. Increasing the length of the overlap, decreasing the adhesive thickness, and the presence of spew fillet improved the joint resistance. The stress distributions from the numerical modeling showed very good agreement with the results of the analytical model. The numerical and analytical models were used to interpret the experimental results.