Influence of the Arrangement of Mechanical Fasteners on the Static Strength and Fatigue Life of Hybrid Joints

Abstract

This paper presents the results of experimental research and numerical calculations regarding the static strength and fatigue life of hybrid joints. In the experiments, specimens built as single-lap adhesive–mechanical joints (hybrid joints) were tested. In a two-stage process of the failure of the hybrid joints, the adhesive joint was damaged first. Therefore, it was assumed that the assembly of fasteners closer to the edge of the overlap (beyond the ranges recommended for mechanical joints) limits the negative impact of the peeling phenomenon on the strength and performance properties of hybrid joints. The specimens used in the experiments were prepared from composite elements (i.e., carbon fiber-reinforced polymer (CFRP)), as well as from the aluminum alloy 2024T4. Because the detection of fatigue damage in composite materials is a complex problem, computed tomography was used to evaluate the degradation of the composite material. Experimental and numerical comparative analyses of the static strength and fatigue life of hybrid joints with adhesive and mechanical joints confirmed the assumptions made.

Mechanistic Study of Failure in CFRP Hybrid Bonded–Bolted Interference Connection Structures under Tensile Loading

“…In large composite structures, connecting composite materials with other relevant materials is a necessity. The most commonly used methods for connecting composite materials in industrial settings are adhesive bonding and using bolted connections and hybrid connections [1,2]. Compared to traditional bolted and adhesive connections, hybrid bonded-bolted connections can enhance structural connection performance such that is meets the requirements of aerospace equipment [3][4][5].…”

Temperature Rise of an Adhesive Particle-Reinforced Polymer during Fatigue Testing

“…With the increase of temperature, the Young’s modulus and tensile strength decrease, but the ductility of the polymer increases [ 18 ]. Often, even a minor change in temperature causes a significant change in these properties [ 19 ]. In the case of variable loads, the very nature of the load may cause the temperature of the adhesive bond joint to rise by 20–30 °C or even more.…”

Numerical and experimental investigation on the load‐bearing performance of plain‐woven composites hybrid bonded‐bolted joints

“…In the numerical study of CFRP joint, homogenization modeling methods on traditional laminate composites have been primarily used in finite element simulation, 25,26 among which Roskowicz et al 27 performed several simulations and experiments to investigate hybrid joints' static strength and fatigue life, besides explaining the damage process by scanning the damage state using computer tomography. Zhang et al 28 examined the effect of bond line thickness on the mechanical properties of hybrid joints of plain-woven CFRP.…”