A metal-composite joint and its mechanical performance

Аuthors

Liu L. , Shi J. , Bao H.

School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Shanghai, China

Abstract

A jointing technique, which can be employed in metal-composite joints and may enhance the ability to non-admission of joints disbond, is proposed in this article. This type of joints will contain a certain number of thin pins running though the substrates in the overlap region of the metal-composite adhesive bonded joints. There is adhesive on the surface of the pins and thus, the pins are bonded together with the substrates. And thus, the pins running through the joint plates not only arrest the cracks in the adhesive layer of the bonded joints, also transfer some load between the metallic and composite components. Comparative test results show that the proposed joint method can increase the strength, the failure strain of the metal-composite joints comparing with the traditional adhesive joints, moreover, the joint method can decrease the suddenness of the joint significantly and therefore, improve the damage tolerance performance of the bonded joints. Secondly, the effects of the number and arrangement of the pins on the mechanical performance of the joint will be analyzed in accordance to the test results also. And finally, an optimized method which can improve the load capacity and fracture toughness of the joints will be obtained.

Keywords:

metal-composite joint, composite materials, finite element models, mechanical performance, metallic pins

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