This study reports the synthesis of multilayer Ti ₃ C ₂ T _x MXene through selective etching of Ti ₃ AlC ₂ and its incorporation into Elium ^® thermoplastic resin at loadings of 0.25–1.0 wt.%. The resulting nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, and mechanical tests, including tensile (ASTM D638), flexural (ASTM D790), and fracture toughness (ASTM D5045) analyses. The 0.75 wt.% MXene composite exhibited the most balanced performance, achieving a tensile strength of 69.45 MPa, a flexural strength of 110 MPa, and a 31% improvement in fracture toughness over neat Elium ^® . These enhancements were attributed to uniform nanofiller dispersion and effective interfacial interaction that facilitates stress transfer and crack deflection. SEM fractography revealed a transition from smooth, brittle fracture surfaces in the neat matrix to rough, branched crack paths in the MXene-filled composites, indicating improved energy dissipation. Overall, MXene/Elium ^® nanocomposites showed superior strength, toughness, and thermal stability, highlighting their potential as lightweight and recyclable materials for structural applications in automotive, aerospace, and protective sectors.

This study investigates the mechanical alloying of silver (Ag) and copper (Cu) nanoparticles with pre-alloyed micro-sized NiTi powders and the characterization of the produced powders both as their powder and sintered forms. Nanocomposite powders with constant Cu content (2.5 wt%) and a variable Ag content (0.5 to 2.5 wt%) were mechanically alloyed in a planetary ball mill and analyzed by XRD, FESEM and EDS methods. The production process involved the dispersion of Cu and Ag nanoparticles in alcohol to obtain a homogeneous distribution, followed by mechanical alloying. The alloyed NiTiCuAg powders obtained by mechanical alloying were compacted using a hydraulic press and subjected to sintering at 1100 °C. Vickers hardness, microhardness and compressive strength tests were performed on the sintered samples. The fracture toughness was determined using Vickers indentation under a 50 kg load. The results showed that the sample containing 2.5% Cu and 1.0% Ag in alloys with different compositions had optimal mechanical properties. The increase of Ag ratio beyond 1.5% causes weakness in mechanical properties. Overall, the addition of Cu and Ag nanoparticles to the NiTi matrix improved the mechanical properties up to a certain Ag content. Based on this, future studies will be followed to investigate the antibacterial properties of NiTi(Cu_2.5, Ag_1.0) nanocomposite alloys.

This study investigates the potential of mechanically processed tea stem waste powders as an environmentally friendly reinforcement for epoxy-based composites. Tea stem waste, a lignocellulosic byproduct of tea processing, was reduced in size by high-speed mixing and planetary ball milling without any chemical pretreatment, and incorporated into an epoxy system at varying weight fractions (1–10 wt.%). The composites were fabricated under controlled conditions and subjected to tensile, fracture toughness, hardness, thermal, and morphological evaluations. Mechanical testing revealed that tensile strength increased with filler loading up to an optimum of 7.5 wt.% (72.16 MPa), corresponding to a 14.8% improvement over neat epoxy, while higher content(10 wt.%) showed minor reduction due to potential filler agglomeration. The elastic modulus displayed a non-linear trend, decreasing slightly at low filler levels but reaching 1.30 GPa at 10 wt.%. Fracture toughness (Kıc) exhibited a continuous increase, with a maximum of 2,41 MPa√m at 10 wt.%—a 26.4% improvement compared to neat epoxy. Shore D hardness also improved progressively, with up to a 23% increase at the highest filler content. Thermal analysis confirmed that the addition of tea stem powder did not significantly affect the glass transition or initial degradation temperatures, while an increased char yield indicated enhanced thermal stability. FE-SEM fractography showed that fiber orientation strongly influenced crack propagation: longitudinal fibers remained intact, while transverse fibers fragmented and dissipated energy, thereby enhancing fracture resistance. These results confirm that tea stem waste powders, processed solely by mechanical means, can effectively reinforce epoxy matrices. Although samples made with 7.5% filler yield the best results in tensile testing, it has been observed that 10% content yields higher results in fracture toughness and hardness tests. The results of the study showed that the mechanical strength of the composite material made from this tea stem waste was higher than that of pure epoxy in all content variations tested here.

The objective of this study is to investigate and compare two different reinforcement routes for epoxy-bonded AA2024-T3 aluminum joints: direct incorporation of multi-walled carbon nanotubes (MWCNTs) into the epoxy matrix and interleaf-based reinforcement using electrospun PVA/MWCNT nanofiber mats. The novelty lies in the direct comparison of these two approaches within the same bonded-joint framework under both shear and Mode I fracture loading conditions. Neat epoxy was used as the reference, while an epoxy with 1 wt.% MWCNT represented the direct nanotube-reinforced system. In the interleaved configurations, the epoxy matrix remained MWCNT-free and the reinforcement was provided solely by PVA nanofiber mats with or without 1–5 wt.% MWCNT. Electrospun nanofiber mats with an average thickness of approximately 0.13 mm were obtained, and the nanofiber diameters decreased from 222–403 nm to 95–192 nm with the addition of MWCNTs to the PVA solution. In single-lap shear tests, the maximum load value was 7804 N for neat epoxy, increased to 8824 N for the epoxy system containing 1 wt.% MWCNT, and reached 9437 N for the joints using a PVA nanofiber mat containing 1 wt.% MWCNT. Joint toughness increased from approximately 1204 kJ/m $$^3$$ to 1954 kJ/m $$^3$$ for the hybrid system with 3 wt.% MWCNT, but decreased at higher MWCNT contents, which may be associated with less uniform dispersion and local defect formation. In double cantilever beam tests, the EPCNT1 sample exhibited an average $$G_{Ic}$$ increase of about 231% relative to neat epoxy.

This study presents the fabrication and characterization of sustainable hybrid epoxy nanocomposites reinforced with tea stem waste powder and 0.5 wt % boron nitride nanoplatelets (BNNPs). The tea stems were ball-milled to an average of 70 μm and added to the epoxy matrix in proportions ranging from 1 to 10 wt % relative to the epoxy resin. The mechanical performance was evaluated using Shore D hardness, tensile testing, and single-edge notch bending, while the thermal and viscoelastic behaviors were examined through dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analyses. The hybrid composites exhibited significant enhancements compared with neat epoxy: Shore D hardness increased from 79.40 to above 97.00, tensile strength reached 63.09 MPa at 7.5 wt % tea stem, and fracture toughness improved from ∼1.70 to ∼2.10 MPa·m^1/2. DMA revealed a clear glass transition at 94–97 °C, along with nearly double the storage modulus in the glassy region of the E-10 sample. The TGA results demonstrated increased thermal stability, with the residual char increasing to 9.58% for E-5. Although both 7.5 and 10 wt % tea stem contents yielded strong improvements, 7.5 wt % provided the best balance of strength, toughness, and filler efficiency. Overall, the findings show that untreated tea stem waste can be effectively combined with BNNPs to develop cost-efficient and environmentally friendly hybrid epoxy nanocomposites.