Effect of Adhesive Types and Fiber Orientation on Mechanical Properties of Single Lap Joint Composite Using Vacuum-Assisted Resin Infusion Manufacturing Method

Composite materials have been widely used in various industries due to their high specific strength and stiffness. Although composite materials have the flexibility to create designs with good integrity, connections between structures may have to be made due to the design of the structure and the cost of the manufacturing process. This paper will evaluate especially the shear strength of composite joints using the single-lap joint method with various adhesive types and ply stacking orientation face of the joint. The composite was made using a vacuum-assisted resin infusion manufacturing technique using carbon fiber and chempoxy resin with specific unidirectional, orthotropic, and quasi-isotropic arrangement orientations. The results showed that the using of the same adhesive as the composite resin type, chempoxy adhesive had the highest value a lap shear strength of 11,43 MPa compared to other adhesives with tested interface layer 0°. The variation of the direction interface layer is a variable that has a significant effect on lap shear strength. The results showed that the quasi-isotropic with interface layers 0°, 90°, and +45 ° has lap shear strength of 7.42 MPa, 6.34 MPa, and 5.46 MPa respectively. The difference in shear strength values in lap joints with variations direction of stacking ply in the interface layer of the adhesive is also evident from the failure modes that occur in the specimens.