Improvement Of Mechanical Properties Research Articles

Enhancing Cassava Starch Bioplastics with Vismia guianensis Alcoholic Extract: Characterization with Potential Applications

This work investigates the incorporation of Vismia guianensis alcoholic extract (EAVG) into cassava starch, with the aim of improving its bioplastic properties. Cassava starch was dissolved into distilled water and doped with 0.2%, 0.5%, and 1.0% EAVG under a temperature controlled at the gelatinization point (∼70 °C) and then cast to form bioplastics. The resulting samples were characterized via attenuated total reflectance/Fourier transform infrared spectroscopy (ATR/FTIR), thermogravimetric and differential thermal analysis (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), atomic force microscopy (AFM), and mechanical essays, providing insights into chemical composition, thermal stability, crystallinity, surface morphology, and mechanical properties. The results demonstrated that EAVG played an effective role, enhancing the flexibility and stability of the bioplastic with potential use in biomedical applications. Moreover, the results also showed significant improvements in mechanical and thermal properties, suggesting that EAVG is a valuable addition to bioplastics. Therefore, EAVG presents a pathway for advancing bioplastics with enhanced mechanical, thermal, and functional characteristics, with the potential for further advancements in these fields.

Improvement of mechanical properties and oxidation resistance of wood ceramics and their use for PM2.5 filtration

Improvement of mechanical properties and oxidation resistance of wood ceramics and their use for PM2.5 filtration

Improvement of microstructure and mechanical properties of Mg-4.5Al-2.5Zn alloy by changing second-pass cross-rolling reduction and cryogenic treatment

Improvement of microstructure and mechanical properties of Mg-4.5Al-2.5Zn alloy by changing second-pass cross-rolling reduction and cryogenic treatment

Effect and mechanism of the salt-alkali composite for the improvement of the early mechanical properties of high-content fly ash-based filling materials

Effect and mechanism of the salt-alkali composite for the improvement of the early mechanical properties of high-content fly ash-based filling materials

Dual phase reinforced CuCrZr alloy: Synergistic improvement of mechanical properties and corrosion resistance via metallic glass and rare earth oxides

Dual phase reinforced CuCrZr alloy: Synergistic improvement of mechanical properties and corrosion resistance via metallic glass and rare earth oxides

Effect of increased basalt fibre dosage on hybrid basalt fibre reinforced concrete's strength properties

Natural, eco-friendly fibers are increasingly being used as reinforcement in the creation of lightweight, low-effort polymer composites on a global scale. Because it is intelligent and has unique properties above glass fibers (GF), basalt fiber (BF) is one such material of interest that is currently in widespread use. Among these composites' clear advantages are their high specific mechanic properties, biodegradability, and non-grating nature. In this paper, basalt fibers used as reinforcement for composites are surveyed. The study also addresses how concrete's strength is affected by curing. In addition to this, an attempt is made to highlight the growing trend in research dissemination and activity in the area of basalt fibers. Further segments talk about the improvement in mechanical, warm and synthetic safe properties accomplished for applications in specific enterprises. The results of this study reveal that the optimum value of strength at 28th day of curing is obtained for a mix made with 5% of chopped basalt fiber 50% 6mm Long BF and 50% 12mm Long BF.

A highly transparent cellulose film for shielding ultraviolet and high-energy visible blue light.

The ultraviolet (UV) and high-energy visible blue (HEVB) light can cause damage to the eyes and skin. In this study, a cellulose composite film with UV and HEVB light shielding properties was prepared through the incorporation of a shielding agent into a carboxymethyl cellulose (CMC) solution. The shielding agent was synthesized through a Schiff base reaction between vanillin (VA) and 3-aminopropyltriethoxysilane (APS). The composite films exhibited excellent shielding performance against UV and HEVB light and maintained high visible light transmittance. Additionally, the films achieved shielding ratios of 100% for UV (200 to 400nm) and 93% for HEVB (400 to 450nm), respectively. Even under prolonged UV irradiation, the composite films maintained excellent shielding stability. The composite films exhibited higher performance in blocking UV and HEVB light than commercial shielding films. Moreover, the composite films achieved 100% antibacterial efficiency against both Staphylococcus aureus and Escherichia coli, even with minimal amounts of the shielding agent. Furthermore, the films exhibited significant improvements in thermal stability, oxidation resistance, and mechanical properties. The multifunctional UV and HEVB shielding films have broad potential applications in food packaging, anti-UV/HEVB radiation display screens, and mobile phone screens.

Development of pH-Responsive SA/PEGDA/AS-POSS Hydrogels via Michael Addition for Controlled Drug Release and Enhanced Mechanical Properties.

In this study, thiolated sodium alginate (SA) and hydrophilic, polymerizable Janus-type polyhedral oligomeric silsesquioxane (AS-POSS) aresynthesized by introducing thiol and sulfonic acid groups, respectively.A series of pH-responsive SA/PEGDA/AS-POSS nanocomposite hydrogels aresuccessfully prepared through Michael addition reactions between the thiol groups of thiolated sodium alginate and the double bonds in the molecular chains of AS-POSS and poly(ethylene glycol) diacrylate (PEGDA).Thisreaction proceeds rapidly underphysiological conditionswithout requiring initiators or catalysts.As the content of AS-POSS increases, the pore size within the hydrogel decreases, and the network structure becomes denser, with significant improvements in mechanical properties. The hydrogel exhibits excellent pH sensitivity, showing lower swelling in acidic media compared to neutral media, and undergoing hydrolysis and losing stability in alkaline media. Moreover, the incorporation of AS-POSS significantly enhances the drug-loading capacity (85.7%) and encapsulation efficiency (72.1%) of doxorubicin (DOX). The drug is released faster in weakly acidic environments, with a cumulative release rate reaching 80.4%, demonstrating excellent targeting and controlled release properties. Cytotoxicity tests show that the SA/PEGDA/AS-POSS hydrogel has good biocompatibility and exhibits effective tumor-killing ability, indicating its great potential as a drug carrier with promising applications in biomedical materials.

Microstructure Evolution Behaviors and Mechanical Properties of 6082-0.2Zr-0.3Er Alloy During the Pre-Hardened Hot Forming Process

Combining a comparative experimental study and theoretical analysis, the feasibility and corresponding action mechanisms of the pre-hardened hot forming (PHF) process applied to 6082-0.2Zr-0.3Er alloy were discussed. The results indicate that unlike a traditional process, after PHF treatment, both the grains and the precipitates at the grain boundaries show a certain directional arrangement, and the texture coefficients of (220) and (200) are enhanced. Although the average size of the second phase is almost the same, the proportion of the fine second phase in the PHF-treated sample is larger. In addition to shortening the processing time and improving the production efficiency, the PHF process was proven to be beneficial for the improvement in the comprehensive mechanical properties of this 6082-0.2Zr-0.3Er alloy, with the product of strength and elongation increased by about 12.1% under the given conditions. Furthermore, with the optimization of process parameters, the improvement effect is expected to be further enhanced.

Lightweight Aluminum Alloy for Energy Saving Green Vehicle

This study is devoted to the development of lightweight Aluminum alloy to reduce energy consumption and environment pollution in automobile sector. Aluminum alloy shows impressive strength though they are lightweight. The effect of Cu on Al-5.5Zn-2.5Mg-xCu alloy has been studied and improvement in mechanical properties within a range has been observed. The optical microstructure confirmed the formation of Cu enriched brittle phase by solid solution strengthening and it accelerates the hardness and tensile strength. After certain limit strength followed the opposite trend so the material can be used as high strength material when the Cu content will be in a certain limit. In automobile sector vehicle parts made with this alloy material has less weight than commonly used steel. The total weight reduction of a vehicle will reduce the energy consumption which will ultimately eliminate the emission of environment pollutant gas

Experimental and Theoretical Analysis of Dopamine Polymerization on the Surface of Cellulose Nanocrystals and Its Reinforcing Properties in Cellulose Acetate Films

The study of natural materials inspires sustainable innovations, with biomimetics excelling in surface modification. Polydopamine (PDA) offers a promising approach for modifying cellulose nanocrystals (CNC), enhancing their compatibility with hydrophobic polymers by improving interfacial adhesion. In this work, the modification of CNC with PDA (CNC@PDA) significantly enhanced the compatibility between the nanocargoes and the cellulose acetate (CA) matrix. The CNC@PDA complex formation was suggested through a combination of FTIR analysis, particle size distribution measurements and ζ-potential analysis. However, the exact mechanism behind dopamine polymerization on the surface of CNC remains a subject of ongoing debate among researchers due to its complexity. This study hypothesized the formation of modified CNC through this process. Furthermore, this study provided a satisfactory investigation of the antimicrobial activity of CNC@PDA in response to bacterial strains (E. coli, P. aeruginosa, S. aureus and L. plantarum) in view of the hypothesis of the possible generation of reactive oxygen species (ROS). Additionally, the incorporation of CNC@PDA CA films was analyzed to assess its effect as a mechanical reinforcement agent. The results showed an improvement in mechanical properties, with the 1% CNC@PDA film exhibiting the best balance between tensile strength and flexibility.

Mechanical property strengthening by post-heat treatments in NiTiCu shape memory alloys fabricated by twin-wire arc additive manufacturing

ABSTRACT To address the challenges of wide transformation hysteresis as well as the poor properties of NiTi-based alloys fabricated by twin-wire arc additive manufacturing, post-heat treatments were employed in as-deposited NiTiCu alloys. After aging at 450°C, 550°C, and 650°C, the alloys exhibited significant reduction in the precipitate sizes, narrow transformation hysteresis, uniform distribution of microhardness, and substantial improvement in mechanical properties. With the increase of the aging temperature, the matrix grain size and the precipitate size coarsened, which was detrimental to the resultant mechanical properties. The alloys aged at 450°C exhibited the narrowest transformation hysteresis of 11.7°C and optimal mechanical properties (tensile strength of 539 MPa and fracture strain of 6.9%). The enhancement of mechanical properties can be attributed to the smaller matrix grain size and precipitate size and the higher proportion of high-angle grain boundaries in this material condition. This work provides practical significance for the twin-wire arc additive manufacturing and performance optimisation of NiTi-based ternary alloys.

Improving the Mechanical, Corrosion Resistance, Microstructural and Environmental Performance of Recycled Aggregate Concrete Using Ceramic Waste Powder as an Alternative to Cement

This study investigates the effectiveness of replacing the cement with 0, 5, 10, 15, and 20 wt.% of ceramic waste powder (HCCP) to improve the performance of recycled aggregate concrete (RCA) prepared using 25 wt.% wall tile ceramic coarse aggregates. The slump, initial and final setting time, compressive strength, splitting tensile strength, flexural strength, electrical resistivity, bulk density, porosity, total and surface water absorption, pH level, ultrasonic pulse velocity, dynamic elastic modulus, chloride ion diffusion coefficient, chloride penetration depth, microstructure analysis, and environmental assessment properties were investigated. The results showed that replacing cement with HCCP by 5 to 20 wt.% prolonged the setting time and improved all hardened properties. The highest improvements in mechanical properties were observed at 5 wt.% HCCP, with increasing rates of 26.5%, 22%, and 22.4% at 90 days for compressive strength, tensile strength, and flexural strength, respectively. On the other hand, the optimum enhancement for the durability, microstructural, and environmental efficiency properties was recorded at a 20 wt.% HCCP replacement rate. However, the strength at this ratio tended to decrease but remained higher than that of the control RAC. For instance, the total water absorption, surface water absorption, void ratio, chloride penetration depth, and migration coefficient were reduced by 47%, 45%, 38%, 62.3%, and 55.52%, respectively, compared to the reference sample.

Heat-Responsive PLA/PU/MXene Shape Memory Polymer Blend Nanocomposite: Mechanical, Thermal, and Shape Memory Properties

This study investigates the fabrication and characterization of heat-responsive PLA/PU/MXene shape memory polymer blend nanocomposites with varying PLA content (10, 20, 30, and 50%) and a fixed MXene content of 0.5 wt.%. The results indicate significant improvements in mechanical properties, with the 50% PLA/PU/MXene blend showing a 300% increase in ultimate tensile strength and a 90% decrease in % elongation compared to pure PU. Additionally, the 50% blend exhibited a 400% increase in flexural strength. Microstructural analysis revealed dispersed pores and sea–island morphology in pure PU and the 50% PLA/PU/MXene blend. Thermal analysis using DSC showed an increase in crystallinity from 33% (pure PU) to 45% for the 50% PLA/PU/MXene blend, indicating enhanced crystalline domains due to the semi-crystalline nature of PLA and MXene’s influence on molecular ordering. TGA demonstrated a significant improvement in thermal stability, with the onset temperature rising from 185 °C (pure PU) to 212 °C and the degradation temperature increasing from 370 °C to 425 °C for the 50% blend, attributed to the rigid structure of PLA and MXene’s stabilizing effect. Shape memory testing revealed that the 30% PLA/PU/MXene blend achieved the best shape fixity and recovery with optimal performance, whereas higher PLA content diminished shape memory behavior.

Strong and tough polyvinyl alcohol hydrogels with high intrinsic thermal conductivity

Although polyvinyl alcohol (PVA) hydrogels display huge potential in tissue engineering, flexible and wearable electronic devices and soft robotics, their low intrinsic thermal conductivity and weak mechanical properties severely limit their wider applications in these areas. Herein, a Hofmeister effect-assisted “directional freezing-stretching” tactic is employed for simultaneously enhancing the intrinsic thermal conduction and mechanical properties of PVA hydrogels. The hydrogels are obtained through directional freezing followed by salting-out treatment and subsequent mechanical stretching and salting-out (DFS). The DFS PVA hydrogel with 15 wt% of PVA and a stretching ratio of 4 (DFS4) exhibits the highest thermal conductivity of 1.25 W/(m·K), which is 2.4 and 2.8 times that of PVA hydrogel prepared through frozen-thawed (FT) [0.52 W/(m·K)] and frozen-salted out (FS) [0.45 W/(m·K)] methods, respectively. The DFS4 PVA hydrogel also possesses greatly improved mechanical performances, exhibiting an elongation at break of 163.1%. In addition, the tensile strength, toughness, and elastic modulus of DFS4 PVA hydrogel significantly increase to 27.1 MPa, 25.3 MJ·m-3, and 21.5 MPa from 0.4 MPa, 0.32 MJ·m-3, and 0.07 MPa for FT PVA hydrogels, respectively. It is elucidated that the salting-out effect generates hydrophobic and crystalline regions, while directional freezing and stretching enhance the chain orientation in the DFS strategy. These effects synergistically contribute to the improvement of thermal conductivity and mechanical properties of PVA hydrogels.

Improvement of Mechanical Property and Room Temperature Wear Resistance of AlTiN Coating Through Low Content Co-Addition of Cr and Si Elements

Improvement of Mechanical Property and Room Temperature Wear Resistance of AlTiN Coating Through Low Content Co-Addition of Cr and Si Elements

Improvement of the Wear and Corrosion Resistance of CrSiN Films on ZE52 Magnesium Alloy Through the DC Magnetron Sputtering Process

The utilization of magnesium alloys as lightweight structural materials is becoming increasingly prevalent, particularly within the fields of electronics, automotive engineering, and defense. These alloys display high specific strength and excellent heat dissipation properties. The magnesium–zinc–rare earth alloy ZE52 displays superior formability and strength-ductility when compared to conventional magnesium alloys. A CrSiN film was deposited on the surface using a sputtering technique with the objective of enhancing wear and corrosion resistance for industrial applications. A CrSi buffer layer was deposited onto the ZE52 substrate prior to the deposition of the CrSiN film, with the objective of enhancing the adhesion between the two materials. The sputtering process for CrSiN films entailed the modulation of the substrate bias voltage. The CrSiN films exhibited a nanocomposite structure comprising CrN nanocrystallites embedded within an amorphous Si3N4, which resulted in enhanced hardness. Upon adjusting the bias voltage, improvements in mechanical properties were observed, with the film hardness and Young’s modulus increasing to 16.5 GPa and 187.4 GPa, respectively. Among the various CrSiN coatings under investigation, the ZE52 alloy that was coated with a CrSiN film deposited at a bias voltage of −50 V and a substrate temperature of 250 °C demonstrated the most favorable performance, exhibiting the lowest wear rate and superior corrosion resistance. In the tungsten carbide wear test with a loading of 4 N, the coating exhibited the lowest wear rate, at 2.2 × 10−6 mm3·m−1·N−1. Furthermore, the coating demonstrated remarkable corrosion resistance in a 3.5% NaCl solution, displaying a corrosion current density of 1.23 μA·cm−2 and a polarization resistance of 1271.4 Ω·cm−2.

Environmental Friendly Polymer Based Recycled Nitrile Gloves Incorporated With Poly(Lactic Acid)/Graphene Nanoplatelets Binary Blends

ABSTRACTThe waste issue from the widespread use of nitrile gloves emphasize the environmental and health risks associated with improper disposal. This study introduces an innovative approach by incorporating recycled nitrile gloves made from acrylonitrile butadiene (rNBR) into a composite with poly(lactic acid) (PLA) and graphene nanoplatelets (GNPs) (1, 2, and 3 phr). The results showed a maximum improvement in mechanical properties at a PLA/rNBR blend ratio of 60:40 wt%, demonstrating a balance between stiffness and toughness compared to other binary blend ratios. The incorporation of GNP enhanced the values of Young's modulus, tensile strength, and elongation, respectively. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) recorded that the thermal stability of PLA/rNBR tends to increase with the loaded GNP. The morphological properties observed through scanning electron microscopy (SEM) revealed that the PLA/rNBR surface exhibited a nonhomogeneous distribution, leading to the formation of numerous voids and low adhesion. However, the good distribution of GNP within the matrix contributed to greater homogeneity, thereby reducing defects caused by rubber crumbs and voids in the PLA/rNBR fracture. Based on this research, this strategy offers a promising solution to address the environmental challenges posed by personal protective equipment waste.

Processing of Ti–5Al–4W–2Fe Alloy Using Different Powder Metallurgy Routes to Improve Its Implementation in Structural Applications

Abstract Titanium (Ti) alloys can be thoroughly improved by introducing aluminum (Al) as an $$\alpha$$ α -phase stabilizer and tungsten (W) as a $$\beta$$ β -phase stabilizer as well as iron (Fe) for enhancing the strength and the creep resistance. In the current study, Ti–5Al–4W–2Fe alloy was especially synthesized to meet the essential requirements of the structural products of Ti-based alloys. Three different PM routes have been adjusted for investigating both densification and mechanical properties improvement of this alloy. The first approach was pressure-less vacuum sintering (PLS) at 1100–1300 °C for 1 h, which showed inadequate achievement of densification. Unfortunately, using PLS 96% of the theoretical density (TD) was recorded. However, using hot pressing (HP) and sintering-forging (IF) resulted in a successful full densification of 100% TD. It is worth mentioning that adding W particles resulted in an effective grain refinement of the sintered Ti alloy. More interestingly, HP-sintered specimens demonstrated higher strength and plastic compression compared to the other specimens. For instance, the yield and fracture strength of this specimen showed 1463 MPa and 2408 MPa, respectively, which is considered as a remarkable achievement compared to similar studies. Surprisingly, the most economical technique PLS sintering led to the best hardness of 700 HV, compared to 470 HV and 480 HV for the forged specimen and the HP-sintered specimen, respectively.

Exploitation of Perennial Plant Biomass for Particleboards Designed for Insulation Applications.

With rising demand for wood products and reduced wood harvesting due to the European Green Deal, alternative lignocellulosic materials for insulation are necessary. In this work, we manufactured reference particleboard from industrial particles and fifteen different board variants from alternative lignocellulosic plants material, i.e., five types of perennial plant biomass in three substitutions: 30, 50 and 75% of their share in the board with a nominal density of 250 kg/m3. Within the analysis of manufactured boards, the mechanical, chemical and thermal properties were investigated-internal bond, formaldehyde emissions, thermal insulation, heat transfer coefficient and thermal conductivity. In the case of thermal conductivity, the most promising results from a practical point of view (W/mK < 0.07) were obtained with Sida hermaphrodita and Miscanthus, achieving the best results at 50% substitution. The lowest formaldehyde emissions were recorded for boards with Panicum virgatum and Miscanthus, highlighting their positive environmental performance. In terms of mechanical properties, the highest internal bond was noticed in particleboards with a 30% substitution of Spartina pectinata and Miscanthus. Research findings confirm the potential of perennial plants as a sustainable source of raw materials for insulation panel manufacturing. Despite needing improvements in mechanical properties, most notably internal bond strength, these plants offer an ecologically responsible solution aligned with global construction trends, thus lessening reliance on traditional wood products. Thus, long-term benefits may be realized through the strategic combination of diverse raw materials within a single particleboard.