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• S-core sandwich panel composites design and manufacturing were done. • Finite element modeling and mechanical tests were performed in three-point bending. • Bending behaviors were compared. Sandwich panel composites have numerous applications in material technology. The sandwich panel composite structure's mechanical behavior and performance are determined by the material properties and geometry of the relevant components. The top and bottom sheets of the designed sandwich panel composite material are made of stainless steel-316, the core material is aluminum 1050A-0, and the binding element is DP-8405 acrylic adhesive. Three-point bending tests and finite element models were utilized to investigate the bending behavior of S-core composite sandwich panels. Finite element models have been developed to characterize the effect of composite element bending behavior on variations. The specific flexural modulus and strength of composite S-core sandwich structures can be compared to core structures in the literature in general. As a consequence, the minimum weight design was used as a guideline to produce weight and density-efficient hybrid composite sandwich panels. The load-carrying capacity of the composite panel increased as the wall thickness of the S-shaped core increased when the damage loads were examined in the variations. It has been ascertained that as the core height increases, the load-carrying capacity of the composite panel decreases. [ABSTRACT FROM AUTHOR]

Abstract: The stresses and deformations in the shrink-fitted hub–shaft joint for various fit forms have been analysed using finite element method. First, the results of finite element method (FEM) were compared with the results of Lame’s equations along central radial line of one shrink fit type for accuracy of model and it was proved by these results. Then, the most appropriate fit type was investigated. It was observed that the most effective parameter to determine appropriate fit type is to be stepped or not for shaft and the geometries of hub of which edges were wasted have been found as more appropriate to reduce the stresses and deformations. Finally, it was also observed that the each point of the shaft or the hub at the moment of the first meeting to its partner during fit can enter the plastic region, and this situation must be taken into consideration as design parameter. [Copyright &y& Elsevier]

Abstract In this study, single lap joints were formed by adding nano-Al 2 O 3 , nano-TiO 2 and nano-Al 2 O 3 powders in various proportions to the epoxy adhesive and using the additive-free epoxy adhesive; and also the mechanical properties of the connections were experimentally investigated at 20, 25, 30, 50 and 70 mm overlap lengths under shear load. In the experimental work, DP460 epoxy adhesive was used as adhesive and AISI 304 stainless steel plate as adherent material. When the results obtained from the experiments were examined, it was revealed that the average damage load in connection with the use of nanoparticle-added adhesives increased considerably in general. As a result of the experiments, the most effective nanoparticle in increasing the failure strength of the adhesive joints with nano-Al 2 O 3 particles and the maximum failure strength increase rate was 20 mm in overlap length and 97% in 4 wt% nano-Al 2 O 3 reinforced specimens. It was also found that the nanoparticle strain was an important parameter in the tensile strength of the adhesive joints. In addition, it has been found that the addition of nanoparticles into the adhesive increases the elongation of the joints. When the adhesion surfaces of the samples were examined as in the case of plain adhesives, damage was observed as adhesion separation while nanoparticle reinforcement was observed as a mixture of adhesion and cohesion. Graphical abstract Image 1 Highlights • Behaviour of nano-particle used in the adhesive joints was analyzed by experimental. • The effects on the tensile strength of nano-particles were investigated in single lap joints added nano-particle. • Three type nano-particles are used to mix with adhesive. • Experimental analyses were carried out to predict the failure loads. • The maximum failure strength increase rate was 20 mm in overlap length and 97% in 4 wt% nano-Al 2 O 3 reinforced specimens. [ABSTRACT FROM AUTHOR]

Abstract Because of their many advantages, adhesively bonded joints are intensively used in many engineering fields. So, the mechanical research of the adhesively bonded joints is very important to use these joints safely. There are many studies performed by researchers to investigate the mechanical properties of the adhesive joints. There has been a considerable interest in nanoparticles added to structural adhesives recently because nanoparticles improve the mechanical properties of adhesives and joints. In this paper, different nanoparticles reinforced by epoxy adhesive, and neat adhesive were used to produce single lap joints. The static and fatigue strengths of single lap joints incorporating nanoparticles were compared to those without nanoparticles. Experiments were performed at 20 mm overlap length. DP460 epoxy was used as the adhesive material, and nano-Al 2 O 3 , nano-TiO 2 and nano-SiO 2 were used as the nanoparticles; and AISI 304 stainless steel plates were used as the adherents. The results of the experimental research revealed that average failure load increased significantly in nanoparticle-reinforced adhesive joints. The highest average failure load was obtained with 4 wt% nano-Al 2 O 3 in epoxy adhesive. Fatigue tests were performed at 10 Hz frequency, and 0.1 loading ratio (R). When the fatigue test results were examined, it was observed that the addition of the nano-Al 2 O 3 and nano-SiO 2 to the adhesive increased fatigue strength of the adhesive joints, on the other hand, the addition of the nano-TiO 2 to the adhesive reduced fatigue strength of the adhesive joints. Graphical abstract Image 1 Highlights • Behavior of nano-particle used in the adhesive joints was analyzed as experimental. • The effects of nano-particles were investigated in the single lap joints on the static and fatigue strength. • Three type nano-particles are used to mix with adhesive. • The highest average failure load was obtained with 4 wt% nano-Al 2 O 3 in epoxy adhesive. • It was observed that the addition of the nano-Al 2 O 3 and nano-SiO 2 increased fatigue strength of the adhesive joints. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, it is aimed to compare mechanical behaviors of T-joint types with embedded and non-embedded supports subjected to bending moment. For this purpose, after experimental studies on the two different T-joint types were conducted, stress analyses in the T-joints were performed with a three-dimensional finite element method by considering the geometrical non-linearity and the material non-linearities of the adhesive (DP460) and adherend (AA2024-T3). Finally, stress analyses and experimental results show that the variation of the geometry of the bonding zone, e.g., embedding the supports, would change the stress distributions and strength of the joint. Additionally, it is seen that T-joints with embedded supports carry 30% more load than T-joints with non-embedded supports although their bending stiffnesses decrease. [Copyright &y& Elsevier]

Abstract: In this study, mechanical properties of adhesively bonded single-lap joint (SLJ) geometry with different configurations of lower and upper adherends under tensile loading were investigated experimentally and numerically. The adherends were AA2024-T3 aluminum and carbon/epoxy composite with 16 laminates while, the adhesive was a two-part liquid, structural adhesive DP 460. In experimental studies, four different types of single-lap joints were produced and used namely; composite–composite (Type-I) with lower and upper adherends of the same thicknesses and four different stacking sequences, composite–aluminum (Type-II) with lower and upper adherends of the same thicknesses and four different stacking sequences, composite–aluminum (Type-III) with lower adherend (composite) of the same thickness but upper adherend of three different thicknesses, aluminum–aluminum (Type-IV) with lower adherend of the same thickness but upper adherend of three different thicknesses, composite–composite (Type-V) with [0]16 stacking sequences and three different overlap length, aluminum–aluminum (Type-VI) with three different overlap length. In the numerical analysis, the composite adherends were assumed to behave as linearly elastic materials while the adhesive layer and aluminum adherend were assumed to be nonlinear. The results obtained from experimental and numerical analyses showed that composite adherends with different fiber orientation sequence, different adherend thicknesses and overlap length affected the failure load of the joint and stress distributions in the SLJ. [Copyright &y& Elsevier]