Abstract
Modern sports equipment demands lightweight materials that can absorb repeated high-energy impacts without failure. Epoxy-based composites are widely applied to golf clubs, tennis rackets, bicycle frames and dance apparatus, owing to their outstanding stiffness-to-weight ratio. However, the inherent brittleness of epoxy remains a major limitation. A golf club head, for example, must withstand the full force of a swing followed by an instantaneous collision with the ball, and any microcrack can quickly propagate toward catastrophic failure. This study explores a hybrid reinforcement approach that combines conventional glass fibers with carbon nanotubes in an epoxy matrix. Glass fibers provide macroscopic load-bearing capacity, while well-dispersed nanotubes impede crack initiation and growth at the nanoscale. By carefully controlling nanotube content and dispersion quality, we aim to shift the fracture behaviour from brittle to ductile, a transition essential for sports equipment that must survive many cycles of use. The practical goal is to develop a material suitable for golf club shafts and heads as well as other sporting goods, where impact resistance directly influences performance, safety, and product lifespan. Our hybrid strategy offers a pathway to reconcile the competing demands of low density, high stiffness, and high toughness. This knowledge is directly applicable to designing next-generation sports equipment that remains light, responsive, and durable under competitive play.
Key Words
sports composites; golf club durability; impact-resistant epoxy; carbon nanotube reinforcement; hybrid glass fiber composites; brittle fracture prevention
Address
Qi Liang, Muhamad Hafiz Bin Ismail, Diyana Zulaika Binti Abdul Ghani: Faculty of Educational Sciences and Technology, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
Mimi Guo, Mostafa Habibi: Department of Mechanical Engineering, Faculty of Engineering, Haliç University, Istanbul, Turkey/ Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, India
Abstract
A hybrid nanolubricant was developed by dispersing MoS2 nanoparticles in graphene-enhanced engine oil to address wear under severe boundary lubrication in racing engines, focusing on colloidal stability and protective interfacial film architecture to prevent phase separation or aggregation under high shear and thermal cycling. XRD and Raman confirmed retained MoS2 phase and carbon presence, while SEM/TEM revealed lamellar MoS2 distribution and intercalation on/between graphene sheets. Turbidity, static holding, and centrifugal tests demonstrated stable dispersion without concentration gradients over time. EDS/XPS verified Mo and S dominance as sulfide species, and FTIR indicated minimal unwanted oxygen groups. The hybrid nanolubricant leverages MoS2's tribological advantages while graphene improves dispersion stability and protective layer durability under racing-like conditions, facilitating translation from laboratory to reliable formulations.
Key Words
boundary lubrication; colloidal stability; dispersion stability; engine oil; graphene; hybrid nanocomposites; MoS2 nanoparticles; nano-lubricants; racing engines; wear reduction
Address
Zhichao Xu: National Civil Engineering Experimental Teaching Demonstration Center, Hunan City University, Yiyang, 413002, Hunan, China/ Field Scientific Observation and Research Station of Geological Environment System for Permafrost Areas in Northeast China, Ministry of Education, Northeast Forestry University, Harbin, 150040, Heilongjiang, China/ Hunan Provincial Engineering Research Center for Structural Safety and Disaster Prevention of Urban Underground Infrastructure, Hunan City University, Yiyang, 413002, Hunan, China
Liangjun Lyu: School of Economics and Management, Lanzhou Institute of Technology, Lanzhou 730050, Gansu, China
Xiao Han: Lawrence Technological University, Southfield, Michigan, 48075, U.S.A
Yunshan Chen: Key Laboratory of Key Technologies for Digital Urban and Rural Spatial Planning of Hunan Province,
Hunan City University, Yiyang, 413002, Hunan, China
Mostafa Habibi: Department of Mechanical Engineering, Faculty of Engineering, Haliç University, Istanbul, Turkey/ Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, India
Touba Zolfaghari: Department of Chemistry, Basic of Sciences Faculty, Ilam University, 69315-516 Ilam, Iran
Amel Boukhlif, Mostefa Lallam, Abdelghani Baltach, Abdelkader Djebli, Mohammed El Sallah Zagane, Murat Yaylaci, Ali Benhamena, Mehmet Emin Özdemir, Hasan Sesli, Ecren Uzun Yaylaci
Abstract
Bonded assembly is a widely used technique especially in the aerospace industry. This work aims to study the behavior of a bonded assembly-type metal/metal under tensile loading. A numerical investigation with the code (FEM Abaqus) was carried out to evaluate the resistance of a single-lap adhesive-bonded joint, highlighting several parameters namely: loading, thickness of adhesive, and overlap length. The geometric model for the single-lap adhesive-bonded joint used is made of two thin steel plates, with different adhesive types. The results obtained by the finite element method show that the optimum overlap length (O-L = 10 mm) is the length of the adhesive that allows it withstand a maximum force for a minimum adhesive surface.
Key Words
adhesive surface; bonded assembly; fem method; joint single lap; overlap length
Address
Amel Boukhlif, Ali Benhamena: Department of Mechanics, Faculty of Science and Technology, University of Mascara, 29000 Mascara, Algeria
Mostefa Lallam: Department of Civil Engineering, Faculty of Sciences and Technology, University of Mascara, 29000 Mascara, Algeria
Abdelghani Baltach: University of Tiaret, Department of Mechanical Engineering, city Zaâroura BP 78, Tiaret 14000, Algeria
Abdelkader Djebli: University of Mascara, LPQ3M Laboratory, Mascara, Algeria
Mohammed El Sallah Zagane: University of Tiaret, Department of Mechanical Engineering, city Zaâroura BP 78, Tiaret 14000, Algeria/ Laboratory LMPM, University of Sidi Bel Abbes, BP 89, City Ben Mhidi, Sidi Bel Abbes 22000, Algeria
Murat Yaylaci: Recep Tayyip Erdogan University, Department of Civil Engineering, 53100, Rize, Türkiye/ Dijitalpark Teknokent, Murat Yaylaci-Luzeri R&D Engineering Company, 53100, Rize, Türkiye
Mehmet Emin Özdemir: 8Cankiri Karatekin University, Department of Civil Engineering, 18100, Çankiri, Türkiye
Hasan Sesli: Yalova University, Department of Civil Engineering, 77200, Yalova, Türkiye
Ecren Uzun Yaylaci: Recep Tayyip Erdogan University, 53100, Rize, Türkiye
Abstract
This study investigates the vibration behavior of carbon nanotube (CNT)-reinforced truncated conical shells subjected to axial loading and internal pressure under elevated temperature conditions. The mechanical properties of the nanocomposite shell are modeled by considering different CNT distribution patterns, including FG V, FG A, FG X, FG O, and uniform distribution (UD). A theoretical formulation based on the first order shear deformation theory is developed to evaluate the vibration characteristics of the structure while accounting for the coupled effects of axial load, internal pressure, and temperature rise. The novelty of the present work lies in the comprehensive investigation of thermo mechanical loading on CNT reinforced truncated conical shells with various functional grading patterns. The results show that the natural frequency increases with increasing axial load, whereas temperature rise leads to a significant reduction in the natural frequency due to the degradation of effective thermo mechanical properties. In addition, the distribution pattern of CNTs plays an important role in controlling the stiffness and vibration response of the shell structure.
Key Words
carbon nanotube; natural frequency; truncated conical shells; vibration
Address
Vahid Ammari, Omid Rahmani, Mohammad Javad Ramezani: Smart Structures and Advanced Materials Laboratory, Department of Mechanical Engineering, University of Zanjan, Zanjan, Iran
Abstract
This study presents a computer-aided design (CAD) methodology for complex nanocomposite roofs of stadiums that experience thermal stress. The proposed large-span roof structure is a multilayer smart composite system composed of a concrete core reinforced with graphene nanoplatelets and piezoelectric face layers that serve two functions: they act as distributed sensors and actuators for structural monitoring and vibration control. Different distributions of the graphene nanoplatelet throughout the thickness of the roof are examined to determine how they affect stiffness, thermal resistance, and dynamic behavior. The structural response of the roof is modeled using an advanced shear deformation theory that models transverse shear effects in thick roof panels without the use of shear correction factors. In order to evaluate realistic thermal loads on the roof, the fractional thermoelastic heat conduction model is utilized for simulating non-local thermal memory and the transient heat transfer characteristics due to varying temperature loads. Fully coupled thermo-electric-mechanical constitutive equations will be used to describe the interaction of the thermal, electrical, and mechanical fields of the smart roof system. The governing equations and boundary conditions are derived using Hamilton's principle and solved numerically via the differential quadrature method with Chebyshev-Gauss-Lobatto discretization. Parametric analyses are performed to study the influence of the distribution of graphene reinforcement, fractions of thermal parameters, thermally-induced loading and piezoelectric coupling on the vibration suppression, energy dissipation and stability of the structure. It was found that this new method of designing a nanocomposite roof using CAD is beneficial to increase the thermal durability, control vibrations and improve the overall structural performance for modern venues.
Address
Liang Mu: Postdoctoral Research Workstation, Harbin Sport University, Harbin 150008, Hei Longjiang, China/ School of Winter Olympics, Harbin Sport University, Harbin 150008, Hei Longjiang, China
Zhenglong Zhang, Zezhong Zhang: Postgraduate School, Harbin Sport University, Harbin 15008, Hei Longjiang, China
Mingyuan Zhao: School of Winter Olympics, Harbin Sport University, Harbin 150008, Hei Longjiang, China
Abstract
This study investigates the bending and stress behavior of functionally graded material (FGM) microplates and shell panels under thermomechanical loading, using the rule of mixtures (ROM) and local representative volume elements (LRVE). The formulation integrates first-order shear deformation theory (FSDT) with the modified couple-stress theory (MCST) to establish a size-dependent framework, and the governing equations are rigorously derived from Hamilton's principle. A neutral surface approach, along with an exact shear correction factor, is used to improve analysis accuracy. A finite element model is developed using an eight-noded isoparametric element with five degrees of freedom per node. The model represents an FGM panel with a pure ceramic upper layer and a pure metal lower layer, where temperature-dependent material properties are graded through the thickness. The effective properties are calculated using the ROM and LRVE. Aluminum oxide (Al2O3) and titanium alloy (Ti-6Al-4V) are selected as the ceramic and metallic constituents, respectively. The accuracy of the proposed formulation is first established by validating it against existing results. Subsequently, a comprehensive parametric analysis explores the effects of key parameters, including the material length-scale ratio, shear correction factor, panel geometry, and boundary conditions, on the structural performance. The findings of this study reveal that size-dependent effects significantly influence the bending behavior and stress distribution of FGM microplates and shell panels under thermomechanical loading. It is also observed that with the use of the exact shear correction factor, the results for bending and stress for FGM microplates and shell panels under thermo-mechanical loading obtained using ROM and LRVE are more accurate than those obtained using the conventional shear correction factor. Notably, the study is useful for microstructural applications involving the thermomechanical analysis of advanced micro-scale engineering structures, such as MEMS devices, sensors, actuators, and resonators, operating under coupled mechanical and thermal conditions.
Key Words
exact shear correction factor; FGM micro plates and shells panels; modified couple-stress theory; static analysis; thermo-mechanical loading
Address
Ankit Kumar, Shashank Pandey: Department of Mechanical Engineering, National Institute of Technology Jamshedpur, Jamshedpur 831014, India
Abstract
This study investigates wave propagation in protein intermediate filaments using advanced beam theories. By formulating a beam model suited to intermediate filaments structural properties, we predict wave speed and frequency, gaining information on their mechanical properties. Our findings reveal intermediate filaments role in cellular mechanics and signaling, providing insight into mechanotransduction and cell-to-cell communication. This study enriches the understanding of cellular biomechanics with relevance to intermediate filaments mutation-related diseases. The phase velocity and frequency versus wave vector are shown in the figures. The comparison of phase velocities versus wave vector and small scale parameter based on non-local Euler Bernoulli and Timoshenko beam model are show in the Tables.
Key Words
atomic force microscopy (AFM); cell mechanics; cytoskeletal dynamics; dispersion relations; mechanotransduction; protein mechanics
Address
Muhammad Safeer, Sabah Javad: Department of Mathematics, University of Poonch Rawalakot 12350, Azad Kashmir, Pakistan
Amien Khadimallah: Prince Sattam Bin Abdulaziz University, College of Engineering, Civil Engineering Department,
BP 655, Al-Kharj, 11942, Saudi Arabia
Muzamal Hussain: Department of Physical and Numerical Sciences, University of Rasul, 50400, Mandi Bahaudin,
Punjab, Pakistan
Natasha Arooj, Rana Muhammad Akram Muntazir: Department of Mathematics, Lahore Leads University, Lahore
Khaled Mohammed Kheder: Department of Civil Engineering, College of Engineering, King Khalid University, Abha, 61421, Saudi Arabia
Abstract
This work addresses the recently developed concept of nanocomposite-reinforced fibers used for improvement of mechanical behavior of sportswear applications. The recent progress in nanomaterials research has allowed incorporating carbon nanotubes, graphene nanoplatelets and other nanomaterials into polymeric matrix of textile fibers in order to achieve a high strength-to-weight ratio, flexibility, and durability under dynamical loads. The effective elastic parameters of nanocomposites are calculated by means of the Halpin-Tsai model that allows estimating the efficiency of the reinforcements at different nanoparticle volume fractions. Quasi-three-dimensional beam theory is applied to account for the transverse shear deformation and stretching of the layer due to its thickness that is essential for analysis of flexible sportswear. The governing dynamic equations are obtained from Hamilton's variational principle providing consistent inclusion of the kinetic and strain energy interaction in the multilayered nanocomposite system. Finally, the Navier solution technique is used for solving the dynamic equations under typical boundary conditions that are specific to sportswear textile structure. Inverse Laplace transform is used to analyze the transient behavior. The presented approach shows promising prospects for the development of wearable materials with impact resistance and mechanical adaptability.
Key Words
dynamic analysis; Halpin–Tsai model; high-performance sportswear; nanocomposite-reinforced fibers; quasi-three-dimensional beam theory
Address
Xiu Yan: Department of Police Physical Education and Tactical Training, Zhengzhou Police College, Zhengzhou 450002, China
