P. Edwin Sudhagar

This experimental study investigates the piezoelectric energy-harvesting performance of composite laminated shell structures for energy-harvesting applications. Thin-walled composite shells were fabricated using hand layup with Glass Fibre Reinforced Polymer (GFRP) composites, and PZT patches...

Adhesive-bonded joints in carbon fiber-reinforced polymer composites offer several benefits, including enhanced flexibility, high specific strength, improved fatigue resistance, and reduced stress concentrations. Consequently, adhesive bonds are often considered more effective than mechanical fasteners. This study explores the impact of incorporating GNPs into the adhesive layer on the properties of secondary-bonded single-lap CFRP joints. These properties include shear and flexural strength, failure mechanisms, and fractography analysis. To improve interfacial strength, six GNP weight percentages 0.25, 0.50, 0.75, 1.0, 1.25, and 1.5 wt.% were tested. The results showed that incorporating 0.75 wt.% GNP increased shear strength by 26.87% compared with the plain adhesive, indicating improved load transfer between adherends. The flexural strength increased by 36.87% with 1 wt.% GNP. Microscopic examination of the fractured specimens revealed that the addition of GNPs roughened the surface, which enhanced the adhesion between the adhesive and adherends.

Composite materials made of fiber‐reinforced polymer (FRP) are utilized in various structural works such as aircraft, wind turbine blades, marine, and automobile industries. The purpose of this research is to investigate the elastic properties of graphene nanoparticles (GNP) added to epoxy (GNP/epoxy) adhesive and glass fiber reinforced polymer (GFRP) using the impulse excitation of vibration technique and also Co‐cure single lap composite plate joint (CC‐SLCPJ) reinforced with GNP/epoxy adhesive to improve elastic properties and stiffness significantly. The results revealed that adding GNP to the epoxy enhances the elastic properties of the GNP/Epoxy. The experimental findings showed that the most significant enhancements in the elastic properties of GNP/epoxy were observed when adding 0.75 wt% of GNP, and the CC‐SLCPJ strengthened with 0.75 wt% GNP/epoxy adhesive showed excellent dynamic behavior. Highlights: Graphene/epoxy adhesive was prepared using the sonication method. The 0.75 GNP/Epoxy properties were higher compared to other GNP/Epoxy. The excitation technique was used to find the properties of GFRP. The single‐lap joint plate is fabricated using the hand layup method. The dynamic behavior of SLJ with the addition of 0.75 wt% GNP was higher.

The investigation focused on the glass fiber‐reinforced polymer (GFRP) composite co‐cure single lap joint (CC‐SLJ) that incorporates graphene nanoparticles (GNP) in epoxy and carbon fiber‐reinforced polymer (CFRP) Z‐pin reinforcement. The flexural test indicated that the integration of GNP and CFRP‐Z‐pin within the inner and outer layers of SLJ leads to improvement in flexural strength. The flexural strength of CC‐SLJ reinforced with GNP/epoxy and Z‐pin reinforcement reaches 145.02 MPa under static loading, with an improvement of 69.55% over the unreinforced SLJ. The SLJ under static loading with GNP/epoxy and graphene incorporated Z‐pin reinforced with demonstrate a significant improvement in flexural strength of 150.34 MPa, with an improvement of 71.22% over the unreinforced SLJ. Fractography revealed that the incorporation of GNP and Z pins into the SLJ enhances interfacial bonding between the adhesive and adherend, increases surface roughness, improves pin pull‐out resistance, and influences crack formation.Highlights: The co‐cure technique is used to fabricate single‐lap GFRP composite joints. Carbon fiber‐reinforced polymer Z‐pin reinforced with GNP/epoxy adhesive. SLJ flexural strength was higher in 1.25 wt% of GNP and 2.5 vol% 90°/Z‐pin. Multiple reinforcements used in SLJ to achieve its maximum flexural strength. Failure analysis was conducted using microscopes and FESEM images.

Adhesive‐bonded joints in glass fiber‐reinforced polymer (GFRP) composite structures give numerous benefits, such as greater flexibility, good specific strength, improved fatigue resistance, and the ability to reduce stress concentration. Consequently, adhesive‐bonded joints are considered more influential if compared to fasteners. This research investigates the effects of incorporating graphene nanoparticles (GNPs) into the adhesive layer on several aspects of adhesively bonded co‐cure (CC) single‐lap GFRP composite joints. These aspects include shear strength, flexural strength, failure mechanisms, and fractography studies. The study examined six distinct weight percentages of GNP, specifically 0.25, 0.50, 0.75, 1.0, 1.25, and 1.5 wt.%, which are considered to enhance the interfacial strength of adhesive joints. Based on the research, 0.75 wt.% of GNP single‐lap joint (SLJ) shear strength improved by 69.40% when compared to the plain matrix SLJ. This suggests excellent load transmission between adherends. In addition, the flexural strength increased by 46.57% in the specimens containing 1.25 wt.% GNP when compared to the plain matrix used to bond in SLJ. After testing, fractured specimen microscopic images were used to examine failure mechanisms. According to fractography studies, adding GNPs to the adhesive causes surfaces to become rougher, which improves the adhesion between the adhesive and the adherends.Highlights: Six distinct wt.% of GNPs were used to prepare the matrix by sonication. Single‐lap GFRP composite joints were fabricated through a CC technique. SLJ's maximum shear strength was found at 0.75 wt% of GNP. SLJ's maximum flexural strength was found at 1.25 wt% of GNP. Failure analysis was conducted using microscopes and FESEM images.

Bio-inspired structures have been commonly used in robotics, aerospace, and bioengineering because of their extraordinary qualities. The present study investigates compressive behavior for bioinspired cores. The experimental compression behavior of the bioinspired cores is supported with numerical analysis. As bioinspired structures are complex in nature, it is difficult to fabricate with the conventional technique. powder bed fusion (PBF) is employed to overcome this difficulty. Further specific energy absorption due to the compression behavior of the bioinspired cores and residual stress induced during the manufacturing process is investigated in detail, and the best-performing bioinspired core is reported in this study.

In recent days, the sandwich structure has created significant evolutionary changes in world technology, which are used in many sectors like automobile, aeronautical, defence, etc., The structural-based studies are evaluated and replaced with the sandwich structure, which contains three layers; a core layer, upper and lower face sheets. This article evaluates the transverse shear modulus of the sandwich core structure of 3D-printed materials. Henceforth the bioinspired structural design is adopted as core structure which is bio-mimicked from the microstructural layer design of the woodpecker's beak. Forming the wavy patterns is incorporated with the conventional honeycomb shape. The edges of the structure’s waviness are modeled as champer edges with the required dimensions. The fused deposition modeling (FDM) process is carried out to bring out the expected sandwich core design. Here, the article speaks about the contest between the various types of materials like polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), high impact polystyrene (HIPS), carbon fiber-polylactic acid (CF-PLA), carbon fiber - acrylonitrile butadiene styrene (CF-ABS), carbon fiber-polyethylene terephthalate glycol (CF-PETG). Each material contains specific properties; Henceforth, each material property is validated by ASTM E1876 standard. The objective is to find the good effectiveness of transverse shear modulus by the Nondestructive process called alternative dynamic method among the 3D-printed Bioinspired materials. In this study, CF-PLA stands ahead to give efficient transverse shear modulus property values. These results can be carried forward to structural development, enhancing the structure's performance as the futuristic pathway.