Fatigue behaviour of metal pin-reinforced composite single-lap joints in a hygrothermal environment

A review on the environmental degradation effects on fatigue behaviour of adhesively bonded joints

“…In theory, this conservative approach aims to ensure that the crack will never occur during the service life of the part. However, in the case of adhesively bonded joints, the threshold value or infinite life is considered as a specific number of cycles, frequently, one million cycles with no crack propagation 2,10,12,13 . In most materials, fatigue loading can cause damage and even the catastrophic failure of structural components at lower percentages of the material's fracture toughness.…”

Fatigue behaviour of composite–composite joints reinforced with cold metal transfer welded pins

“…Thus, many research groups have investigated the effect of reducing these stress peaks with through-the-thickness reinforcements [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Among these are stitched [1,[3][4][5]20], tufted [2] and z-pin reinforced [6][7][8][9] composite-composite joints.…”

“…Among these are stitched [1,[3][4][5]20], tufted [2] and z-pin reinforced [6][7][8][9] composite-composite joints. More recent studies focussed on the use of metallic rods as joining reinforcement [10][11][12][13][14][15][16][17][18][19]. Metallic reinforcements can, in contrast to polymeric yarns, glass or carbon fibres, add to the damage tolerance of the joint by plastic deformation [11,16].…”

“…Results from literature show that through-the-thickness reinforcements can increase the fatigue life of SLS joints [1,10,13,18,20,[30][31][32][33][34]. The most common way to present the fatigue behaviour of SLS joints is a correlation of stress to numbers of cycle at failure, the so-called S-N curve [1,13,18,[30][31][32][33][34]. Aymerich et al showed that by stitching the ends of the overlap region of SLS joints, they could increase the numbers of cycle for both crack initiation and propagation [1,30].…”

A progressive failure analysis model for composite structures in hygrothermal environments

“…Chen [9] examined the effects of hygrothermal cycling upon the performance of a bolted composite joint. Ko et al [10] and Son et al [11] investigated the effects of jagged z-pins and stainless steel pins on the static and fatigue strength of composite single-lap joints in a hygrothermal environment, respectively. The joint strength was improved using z-pins especially at an elevated temperature.…”