Environmental effect on the fatigue degradation of adhesive joints: A review

The role of a sinusoid interface shape on the load bearing capacity and fatigue life of adhesively bonded single lap joints (SLJs) was investigated numerically and experimentally. Aluminium adherends with wavy interfaces were tested under both quasi‐static and fatigue loading conditions. The experimental results showed that the non‐flat SLJs were indeed much stronger than the conventional flat joints. In order to fully demonstrate the advantage of the non‐flat sinusoid SLJ over the conventional SLJ, comparative fatigue tests with different loading levels were performed to determine the durability performance of the SLJs with non‐flat interfaces. The experimental results revealed that the non‐flat SLJ had considerably higher fatigue life than the conventional lap joint.

Section: Fatigue Tests With Different Load Levelsmentioning

confidence: 99%

Fatigue performance of adhesively bonded single lap joints with non‐flat sinusoid interfaces

Ayatollahi

Samari

Razavi

et al. 2017

“…Aiming to predict the process of moisture transport in epoxy resin and composites, several mathematical models have been presented, focusing on the use of concentration‐ and stress‐dependent diffusion coefficients . Some authors consider that a Fickian diffusion model with a constant diffusion coefficient can define the following: the main moisture transport in composites, a concentration‐dependent diffusion coefficient, or a stress‐dependent diffusion coefficient .…”

Section: Introductionmentioning

confidence: 99%

Fatigue performance of single lap joints with CFRP and aluminium substrates prior and after hygrothermal aging

Machado

Marques

Barbosa

et al. 2019

Adhesive bonding has been extensively used to join composites and aluminium alloys in the automotive industry, but a deeper understanding of its fatigue behaviour is still required. This work presents a novel evaluation of the combined performance of joints manufactured with carbon fibre reinforced plastic (CFRP) and aluminium substrates subjected to fatigue loads in the unaged, hygrothermally aged, and dried after hygrothermal aging states. The experimental results allowed to conclude that the fatigue performance of joints can be affected by changes induced by the drying process or losses in the interface strength and that dissimilar combination of substrates sustains higher number of cycles to failure. The fatigue performance of joints with dissimilar substrates was found to be better than that of joints with similar substrates, which can be attributed to the lower stresses acting on the adhesive layer. The presence of water has also noticeably changed the fatigue performance of joints with dissimilar substrates.

“…The static strength of the adhesive joints has been studied extensively. However, it seems that the fatigue strength should be analyzed in more detail . Costa et al reviewed the important factors affecting the fatigue strength of adhesive joints.…”

Section: Introductionmentioning

confidence: 99%

“…However, it seems that the fatigue strength should be analyzed in more detail . Costa et al reviewed the important factors affecting the fatigue strength of adhesive joints. Wang studied the fatigue behavior of adhesively bonded joints in three types of SLJ, butt joint, and scarf joint and emphasized the effects of joint geometric parameters on fatigue strength by changing the stress distribution of joint bond line.…”

Section: Introductionmentioning

confidence: 99%

“…However, it seems that the fatigue strength should be analyzed in more detail. 5 Costa et al 5 reviewed the important factors affecting the fatigue strength of adhesive joints. Wang 6 studied the fatigue behavior of adhesively bonded joints Nomenclature: b, constant parameter of Basquin and SWT equation; c, constant parameter of SWT equation; E, Young's modulus; kN, kilo Newton; MPa, Mega Pascal; N, Fatigue cyclic life; N f , fatigue life; P Max , maximum load at fatigue test; P s , fracture force at fatigue test; Δε c , critical cyclic strain range; ε a , total strain; ε ea , elastic strain; ε f , true fracture strain; ε pa , plastic strain; ε ′ f , fatigue ductility coefficient; σ a , stress amplitude; σ a ε a , SWT parameter; σ f , stress at fracture; σ m , mean stress; σ max , maximum stress; σ ′ f , fatigue strength coefficient in three types of SLJ, butt joint, and scarf joint and emphasized the effects of joint geometric parameters on fatigue strength by changing the stress distribution of joint bond line.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The effect of adherent thickness on fatigue life of adhesively bonded joints

Shahani

Pourhosseini

2018

The effect of adherent thickness on the fatigue performance, fatigue limit, and failure mode of adhesively bonded thin aluminum single lap joint (SLJ) was experimentally and numerically investigated. High‐cycle fatigue tests were performed, and fatigue life was estimated using various fatigue criteria and finite element modeling. Based on the experimental results, increase in adherent thickness leads to increase in fatigue limit. In addition, failure location changes from adhesive to adherent by increasing the adherent thickness. It seems that in adherent failure, selecting a sheet with higher fatigue strength is required to achieve higher fatigue life. Also, based on the analysis of different fatigue criteria, Smith‐Watson‐Topper criterion could predict the joint fatigue life more accurately by considering the mean stress effect and the plastic strain. Finally, as an important result, an unsymmetrical SLJ specimen was evaluated as an industrial case study, and the empirical estimated life was consistent with the experimental results.