Reinforcing effect of lock stitching with small density on the tensile properties of composite T-joints

Chen, Boran; Wu, Dong Yang; Zhao, Jia-jiang; Zhao, Yuan; Wang, Linlin; Li, Xiping; Li, Mengjia; Chen, Puhui

doi:10.1016/j.tws.2022.109411

Cited by 8 publications

(4 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When transverse bending loads are transmitted to the corner area of the T-joint, due to the significantly lower interlaminar mechanical properties of composite materials compared to that is inplane [7], the conventional T-joint may experience failure modes such as bonding interface failure, laminate delamination, and random crack propagation within the triangle filling area [8]. In order to improve the load-carrying capacity of the conventional T-joint, some researchers have adopted methods such as stitching [9][10][11][12], Z-pin [13][14][15], and triangle filling area reinforcement [1,16,17] to delay the failure in interlaminar and triangle filling areas. Moderate stitching and Z-pin can effectively delay and reduce delamination damage to the joint and improve its load-carrying capacity [18], but they may also weaken the in-plane mechanical properties of laminates [19][20][21].…”

Section: Introductionmentioning

confidence: 99%

A Novel Preparation Method of Composite Bolted T-joint with High Bending Performance Based on Prepreg-RTM Co-Curing Process

Zhang,

Luo,

Deng

et al. 2024

Preprint

View full text Add to dashboard Cite

A co-curing resin system consisting of 9368 epoxy resin for prepreg and 6808 epoxy resin for resin transfer molding (RTM) was developed. A corresponding preparation method of novel polymer composite bolted T-joint with internal skeleton and external skin was proposed based on prepreg-RTM co-curing process, and novel T-joints were fabricated. A series of conventional configuration T-joints based on RTM process and T-joints made of 2A12 aluminum alloy were prepared simultaneously. Bending performances were studied on these T-joints experimentally. The results indicate that 9368 epoxy resin and 6808 epoxy resin exhibit good compatibility in rheological and thermophysical properties. The novel T-joints prepared with prepreg-RTM co-curing process show no obvious fiber local winding or resin-rich regions inside, and the interface quality between internal skeleton and external skin is excellent. The main failure modes of the novel T-joint under bending load include separation of skin and skeleton and fracture along the thickness on the base panel; the skeleton carries the main bending load, but there is still load transfer between external skin and internal skeleton through their interface. The internal damages of the novel T-joint are highly consistent with surface damages observed visually, facilitating the detection and timely discovery of damages. The initial stiffness, damage initiation load, and ultimate load of the novel T-joint are 1.65 times, 5.89 times, and 3.45 times that of conventional T-joint, respectively. When considering the influence of density, the relative initial stiffness and relative ultimate load of the novel T-joint are 1.44 times and 2.07 times that of aluminum alloy T-joint, respectively.

show abstract

Section: Introductionmentioning

confidence: 99%

A Novel Preparation Method of Composite Bolted T-joint with High Bending Performance Based on Prepreg-RTM Co-Curing Process

Zhang,

Luo,

Deng

et al. 2024

Preprint

View full text Add to dashboard Cite

show abstract

“…As illustrated in Figure 2, the polymer composite bolted T-joint with configuration (hereafter abbreviated as conventional T-joint) consists of two L ers, a bottom layer, a triangle filling area and outer wrapped skin, where L-s and base panel layers are composite laminates, and the triangle filling area m of resin matrix, short fibers, or twisted fibers [6]. When transverse bending lo mitted to the corner area of the T-joint, due to the significantly lower inte chanical properties of composite materials compared to that is in-plane [7] tional T-joint may experience failure modes such as bonding interface fail delamination, and random crack propagation within the triangle filling area to improve the load-carrying capacity of the conventional T-joint, some rese adopted methods such as stitching [9][10][11][12], Z-pin [13][14][15], and triangle filling a ment [1,16,17] to delay the failure in interlaminar and triangle filling are stitching and Z-pins can effectively delay and reduce delamination damag and improve its load-carrying capacity [18], but they may also weaken the chanical properties of laminates [19][20][21]. Moreover, the filling material in the is still connected to the L-shaped layer through the resin matrix, and the tr area remains a weak position for bearing load, thus the degree of improv mechanical performances of joints by this method is limited [17].…”

Section: Introductionmentioning

confidence: 99%

“…When transverse bending loads are transmitted to the corner area of the T-joint, due to the significantly lower interlaminar mechanical properties of composite materials compared to that is in-plane [7], the conventional T-joint may experience failure modes such as bonding interface failure, laminate delamination, and random crack propagation within the triangle filling area [8]. In order to improve the load-carrying capacity of the conventional T-joint, some researchers have adopted methods such as stitching [9][10][11][12], Z-pin [13][14][15], and triangle filling area reinforcement [1,16,17] to delay the failure in interlaminar and triangle filling areas. Moderate stitching and Z-pins can effectively delay and reduce delamination damage to the joint and improve its loadcarrying capacity [18], but they may also weaken the in-plane mechanical properties of laminates [19][20][21].…”

Section: Introductionmentioning

confidence: 99%

A Novel Preparation Method of Composite Bolted T-Joint with High Bending Performance Based on the Prepreg-RTM Co-Curing Process

Zhang,

Luo,

Deng

et al. 2024

Polymers

View full text Add to dashboard Cite

A co-curing resin system consisting of 9368 epoxy resin for prepreg and 6808 epoxy resin for resin transfer molding (RTM) was developed. A corresponding preparation method for a novel polymer composite bolted T-joint with internal skeleton and external skin was proposed based on the prepreg-RTM co-curing process, and novel T-joints were fabricated. A series of conventional configuration T-joints based on the RTM process and T-joints made of 2A12 aluminum alloy were prepared simultaneously. Bending performances were studied on these T-joints experimentally. The results indicate that 9368 epoxy resin and 6808 epoxy resin exhibit good compatibility in rheological and thermophysical properties. The novel T-joints prepared with the prepreg-RTM co-curing process show no obvious fiber local winding or resin-rich regions inside, and the interface quality between the internal skeleton and the external skin is excellent. The main failure modes of the novel T-joint under bending load include the separation of the skin and skeleton and the fracture along the thickness on the base panel; the skeleton carries the main bending load, but there is still load transfer between external skin and internal skeleton through their interface. The internal damages of the novel T-joint are highly consistent with surface damages observed visually, facilitating the detection and timely discovery of damages. The initial stiffness, damage initiation load, and ultimate load of the novel T-joint are 1.65 times, 5.89 times, and 3.45 times that of the conventional T-joint, respectively. When considering the influence of the density, the relative initial stiffness and relative ultimate load of the novel T-joint are 1.44 times and 2.07 times that of the aluminum alloy T-joint, respectively.

show abstract

“…Damage mainly concentrates within the fillet of the deltoid. [8][9][10] Since improving the adhesive performance of the deltoid significantly enhances the force-bearing performance of the total composite, [11][12][13] plenty of research has been focusing on it. Ekermann et al 6 filled the deltoid with three-dimensional braided prepreg and conducted quasistatic tensile pull-off load test.…”

Section: Introductionmentioning

confidence: 99%

Aminated carbon nanotube enhanced composite T‐joints mediating CFRP load‐bearing capacity improvement

Bai,

Yan,

et al. 2023

Polymer Composites

View full text Add to dashboard Cite

Adhesive bond is the weakest part of carbon fiber reinforced composites (CFRP) force‐bearing structure. Therefore, enhancing the strength of the adhesive bond is key to improve force‐bearing structure. In this study, adhesive strength of the common CFRP T‐joint was enhanced by aminated carbon nanotubes (CNT). To begin with, shear tensile strength of single‐lap‐joint laminated composites with various CNT content was verified, which peaked at 0.5 wt%. It was indicated that the adhesive bond of deltoid is the weakest area in a T‐joint. CNT was applied in the deltoid of composite T‐joint and pull‐off test was conducted to investigate the progress from the initiation and evolution of damage as well as the final failure. The aminated CNT employed in this study formed an effective load transmission through physical engagement and chemical bonding; the addition of 0.5 wt% CNT effectively enhanced tensile strength and toughness, improving mechanical property of the adhesive bond. This study provides a solution to enhance the adhesive area of CFRP load‐bearing structure with CNT, consequently improve the load‐bearing strength of composite.Highlights Aminated CNT is substantially improve the adhesive strength of CFRP T‐joint. Tensile strength and toughness of T‐joint deltoid was optimized by 0.5 wt% CNT. Effective load transmission through physical engagement and chemical bonding.

show abstract

Reinforcing effect of lock stitching with small density on the tensile properties of composite T-joints

Cited by 8 publications

References 40 publications

A Novel Preparation Method of Composite Bolted T-joint with High Bending Performance Based on Prepreg-RTM Co-Curing Process

A Novel Preparation Method of Composite Bolted T-joint with High Bending Performance Based on Prepreg-RTM Co-Curing Process

A Novel Preparation Method of Composite Bolted T-Joint with High Bending Performance Based on the Prepreg-RTM Co-Curing Process

Aminated carbon nanotube enhanced composite T‐joints mediating CFRP load‐bearing capacity improvement

Contact Info

Product

Resources

About