Experimental Investigation of Tensile Strength of Metal-Composite Hybrid Joints Using New Inserts in Comeld Process

The use of common adhesive methods in metal-composite bonding leads to weak joints that are separated with the least load. The purpose of this research is to investigate the increase in the tensile strength of aluminum metal to glass fibers reinforced with epoxy resin using a new combined method that includes the advantages of both adhesive and mechanical (pinning) methods. In this method, the pins embedded in the structure are used as an interface for load transfer, and the aim is to investigate the amount of strength changes with different types of interface pins. Therefore, the pins are passed through them during the layering of composite fibers and then the curing process is completed. Therefore, a part of the metal structure has penetrated between the warp and weft of the composite and it is expected that the strength will increase. Four connection models without pin (pure adhesive), pin with a diameter of 1.2 mm, pin with a diameter of 1.6 mm and pin with a claw with a diameter of 1.2 mm have been evaluated and the results of the strength of the connections have been compared. Tensile test results have shown that this type of connection has a significant increase in strength compared to the sample without pins, and in three types of connections with different characteristics, 335%, 609%, and 421% increase in strength has been observed, respectively. Also, failure occurred gradually in samples with pins and suddenly in samples without pins.