Tensile Strength Research Articles

Mechanical properties of MoW–HfN surrogate cermet fuel for nuclear thermal propulsion

AbstractThe mechanical performance of MoW‐HfN, a surrogate cermet for MoW‐UN Nuclear Thermal Propulsion (NTP) fuel, was characterized from room temperature to 1600°C. The modulus of elasticity and flexure strength were obtained from four‐point bend tests. Those tests revealed a loss of stiffness with increasing temperature and systematic increase in ultimate strength up to about 1400°C. This was followed by loss of ultimate strength and the onset of plastic deformation, attributed to the increased ductility of the MoW matrix above 1400°C. Chevron notch tests show that failure originates from features with a critical flaw size of ∼30 εm, which is comparable to the mean particle size of the ceramic phase. X‐ray diffraction (XRD) and Williamson–Hall (WH) analysis suggest that residual stress may contribute to the observed strength‐versus‐temperature behavior.

Impact of Graphene Nano particles on static and dynamic mechanical properties of basalt-glass fibre reinforced epoxy polymer hybrid composites

ABSTRACT This paper investigates the structure-property relationships in basalt – glass fabric reinforced hybrid polymer composites doped with graphene nanoplatelets. Basalt Glass fabrics were reinforced with 0.2 wt.% − 0.8 wt.% graphene using hand layup and compression moulding to fabricate laminated plates. The mechanical, morphological, and thermomechanical properties were characterised using tensile, flexural, impact, SEM, FTIR, XRD, and DMA testing. Results showed that low graphene loadings of 0.2 wt.% − 0.4 wt.% led to small, isolated graphene platelets decorating the basalt fibres. At 0.8 wt.% loading, extensive wrinkling, folding, and stacking of graphene sheets on the basalt was observed. FTIR revealed increasing sp2 C=C vibrations and XRD showed rising graphene peak intensities with higher loadings. While tensile and flexural strengths improved up to 0.6 wt.% graphene due to efficient stress transfer, impact energy increased consistently until 0.8 wt.% graphene owing to reinforcement effects. DMA exhibited enhanced storage modulus and restricted mobility with more graphene. An optimum graphene loading of 0.6 wt.% was found to maximise the mechanical performance through uniform dispersion and strong interfacial adhesion. The results demonstrate that graphene incorporation can substantially augment the strength, toughness, and thermomechanical properties of the composites at appropriate compositions prior to aggregation.

Durable polymer composites preparation with oxy-delignified banana fiber for automotive parts: A study on mechanical and thermal properties

An innovative process route has been developed to produce modified banana fiber that are used as reinforcement in polypropylene composites for automotive parts. Banana fiber (BF) is modified through, Alkaline peroxide (APF), and oxygen delignification (ODF) treatment to obtain better adhesion and enhanced thermo-mechanical properties. The fiber-reinforced polymer (FRP) composites (10–30 % loading), were prepared through a specified configuration in a co-rotating twin screw extruder followed by injection molding. The results show that the ODF treatment with a 15 % NaOH concentration resulted in an 11-kappa number, which was lower than APF and untreated fiber. The highest improvement in tensile (31.27 ± 2.56) and flexural strength (44.880 ± 1.05 MPa) was achieved for ODF polymer composite and were 20.40 % and 35.6 % higher compared to the untreated fiber. The addition of natural fiber decreased the melt flow index to 7.56 gm/10 min with a slight decrease in hydrophilicity. The thermal stability was increased with enhanced melting, crystallization temperatures, and surface morphology.

Research on the Anchoring Performance of Green and Low-Carbon Anchoring Materials for Urban Rail Transit Foundation Pit Engineering

Abstract. Currently, most anchoring materials used in engineering are ordinary cement mortar, which has a slow hardening process, a prolonged early strength development, and high carbon emissions. In response to this, this paper proposes a new type of green anchoring material. The anchoring performance of this material is verified through indoor and field tests. Indoor tests on the basic properties of the green anchoring material were conducted, determining the optimal water-material ratio to be between 0.25 and 0.30 through tests on fluidity, setting time, and compressive strength. Field tests studied the ultimate bond strength of the new green anchoring material in typical soil-rock composite strata in Qingdao, confirming its rapid-setting and high-strength anchoring characteristics. The application of this anchoring material can reduce carbon emissions and realize the concept of green and low-carbon environmental protection.

Preparation of Phosphorus/Hollow Silica Microsphere Modified Polyacrylonitrile-Based Carbon Fiber Composites and Their Thermal Insulation and Flame Retardant Properties

Since thermal insulation materials with a single function cannot satisfy the increasing requirements for complex usage, the combination of thermal insulation with flame retardancy is desirable in multiple applications. Herein, phosphorous-containing flame retardant modifier (5.0 wt.%, 9.0 wt.%, and 13.0 wt.%) and hollow silica microsphere (130 nm of diameter) were composited with polyacrylonitrile-based carbon nanofibers via electrospinning technique. Electrospun phosphorous/silica/carbon nanofibers (P/HSM/CF) exhibited a uniform and clear fibrous structure (508, 170, and 1550 nm of average fiber diameter) with modified uniform and complete spherical silica. Reduced thermal conductivity (39.9–41.2 mW/m/K) and enhanced limiting oxygen index (29.5–33.5%) were achieved, enabling fire protection grade of fiber membrane from UL-94 V-1 grade to UL-94 V-0 grade efficiently. Moreover, favorable tensile strength (8.64–9.27 MPa) and elongation at break (43.28–48.54%) were obtained, presenting expected applications in structural components. The findings of this work provided a valuable reference for the fabrication of carbon nanofiber-based thermal insulation materials with excellent flame retardant and mechanical properties.

Effect of Process Parameters on the Mechanical Properties of Simultaneous Double-Sided Friction Stir Welding Joints

Currently, conventional single-sided friction stir welding is primarily suitable for joining thin plate aluminum alloys, and its application to thick plates is still challenging in terms of welding efficiency and joint mechanical properties. Simultaneous double-sided friction stir welding (SDS-FSW) is a high-efficiency joining technique specifically developed for welding thick plates. However, there is little research on the influence of SDS-FSW process parameters on the joint mechanical properties. In this study, a 12 mm thick AA6061-T6 aluminum alloy and dual robot welding equipment are used to conduct SDS-FSW experiments exploring the influence of rotational speed ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\omega$$\\end{document} and welding speed v on the mechanical properties and microstructure. The results show that when the welding parameters are ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\omega$$\\end{document} = 800 r/min and v = 60–80 mm/min, smooth and defect-free thick plate aluminum alloy SDS-FSW joints can be obtained, and the macroscopic morphology of the joints is distributed in a “dumbbell” shape. The grain size in the weld nugget zone increases with increasing welding heat input. The microhardness distribution in the joint displays a “W” shape, and the hardness value of the weld nugget zone can reach 67% to 86% of that of the base metal (BM). The junction between the thermo-mechanically affected zone and the heat affected zone is the weakest region of the joint, with the lowest hardness being approximately 51% of that of the BM. When the welding parameters are ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\omega$$\\end{document} = 800 r/min and v = 140 mm/min, the SDS-FSW joint has the highest tensile strength, reaching 78.43% of the BM strength and exhibiting ductile fracture characteristics. This research indicates that acceptable weld strength in thick aluminum alloys can be achieved via the SDS-FSW joining mechanism, highlighting its significant potential for industrial applications.

Investigation of nano-basic oxygen furnace slag and nano-banded iron formation on properties of high-performance geopolymer concrete

Abstract Geopolymers have emerged as promising alternatives to traditional cement-based composites, offering enhanced sustainability and opportunities for recycling industrial waste. The incorporation of waste materials into the binding matrix of geopolymer concrete not only promotes environmental benefits but also significantly improves the overall performance, including mechanical strength, durability, and microstructural integrity of the matrix. This study explores the impact of incorporating varying dosages of nano-basic oxygen furnace slag (NBOFS) and nano-banded iron formation (NBIF) on the properties of high-performance geopolymer concrete (HPGC) that utilizes waste glass as 50% fine aggregate. The research focuses on evaluating both the fresh and mechanical properties, including compressive strength, splitting tensile strength, modulus of elasticity, and flexural strength. Additionally, this study investigated the transport properties of concrete under aggressive environments, such as resistance to chloride penetration, sulfate attack, and sorptivity. The microstructure was examined using scanning electron microscopy. The results demonstrated that the addition of 3% NBOFS and 2.5% NBIF significantly improved the fresh, mechanical, and transport properties of HPGC. These nanomaterials also enhance the splitting tensile strength, flexural strength, and elastic modulus under highly aggressive environmental conditions. The contribution of these nanomaterials to the strength and durability of concrete is particularly relevant in the construction of both substructures and superstructures. Additionally, geopolymer concrete significantly reduces CO2 emissions by eliminating the requirement for ordinary Portland cement and promoting the recycling of waste products, contributing to more environmentally friendly construction practices.

Preparation and the influence of twist factor on cut resistance performance of Kevlar short fiber covered yarn fabric

This research utilized Kevlar short fibre yarn to cover Kevlar and UHMWPE filaments, resulting in six different types of covered yarns and their associated fabrics. The aim of the research was to examine the impact of the twist factor of Kevlar short fibre yarn and the type of covered yarn on the mechanical properties of the yarns and their corresponding fabrics. The results indicated that the KPf covered yarn with a twist factor of 305 exhibited the highest breaking strength at 13.06cN/dtex, approximately 24% higher than the KKf covered yarn. The 225-KPf covered yarn fabric demonstrated peak breaking strength at 1772.01 N. Under similar conditions, KPf coated yarn outperformed KKf coated yarn in terms of tensile strength. However, KKf covered fabrics exhibited superior cutting resistance compared to KPf covered fabrics, with the 385-KKf fabric having the highest resistance at 1117.29 N. The study concluded that increased twist factor factors lead to varied outcomes in tensile performance and cutting resistance due to changes in inter-fiber spacing and cohesion pressure on the short fiber yarn, as well as the influence of material molecular structure.

Investigating the influence of ferric oxide grade alumino‐silicate cenosphere particulates and heat treatment on the microstructural evolution and mechanical properties of Al6061/ferric oxide alumino‐silicate cenosphere (x weight %) composite

AbstractThe main aim of this investigation is to fabricate aluminum 6061 composites with three different weight percentages of ferric oxide grade alumino silicate cenosphere (1 wt.%, 3 wt.%, and wt.%) by the stir‐casting process. The fabricated cast composite and T6 heat‐treated composite is used to obtain a fundamental understanding of various weight percentages of the cenosphere and the influence of heat treatment on the microstructural changes, mechanical characteristics, the mechanism of fracture, and the interface between the aluminum‐matrix and ferric oxide grade alumino‐silicate cenosphere particulates. Tensile and compressive tests with a constant strain rate (0.5 mm ⋅ min−1) were carried out to study the strength and to find a correlation between the various weight fractions of cenosphere and heat treatment. Investigations of the changes in the microstructure of the aluminum ferric oxide grade alumino silicate cenosphere composite and the fractography of the fracture surface are investigated using optical and scanning electron microscope. X‐ray diffraction was utilized to confirm the results obtained from optical and scanning electron microscope analyses for phase characterization validation. A maximum of 30 % increase in hardness value, 20 % increase in tensile strength value, 33 % increase in maximum compressive strength value, and 2 % increase in elongation values are observed in heat‐treated composite when compared to cast composite.

Impact of plastic waste fiber and treated construction demolition waste on the durability and sustainability of concrete

This study explores the mechanical and durability properties of Plastic-Fibre Reinforced Concrete, incorporating hand-shredded plastic fibers sourced from polyethylene bags and PET bottles. Evaluations, including compressive and split tensile strength tests, were conducted on M40 grade mixes containing plastic fibers and 100% treated Construction and Demolition Waste (CDW), comparing them with conventional concrete. The results demonstrate a significant enhancement in strength properties with the addition of 0.25%, 0.5%, 0.75%, and 1% plastic-fibres, alongside the complete replacement of coarse aggregate with CDW, particularly noticeable at both 7 and 28-day curing ages. Although higher fiber dosages led to a slight reduction in compressive by 7% at the optimum percentage of 0.25% of PE and 0.5% of PET, the flexural strengths and split tensile strength exhibited a proportional increase of 11.7% and 18%. Surface analysis via Scanning Electron Microscopy (SEM) and elemental composition determination using Energy Dispersive Spectroscopy (EDS) revealed minimal fiber damage post-exposure, confirming its efficiency and contribution to higher strength and reduced weight loss in optimum mix. This novel approach combines manually recycled plastic waste as fibers with treated CDW, enhancing concrete properties while promoting sustainability. Sustainability analysis indicates that utilizing 100% CDW and plastic fiber contributes to reduced energy consumption, lower carbon emissions, and economic benefits. These findings underscore the potential of integrating non-degradable plastics into concrete mixtures, combined with treated CDW, offering both environmental sustainability and enhanced performance advantages in construction materials.

Optimization of Electromagnetic-Wave Reflectivity Performance of Electromagnetic Shielding Yarn Prepared by Evaporation-Induced Sintering of Ga60.5In25Sn13Zn1.5 Alloy with Nanosilicates.

Electromagnetic interference (EMI) shielding textiles have received widespread attention, and liquid metal (LM) shows superiority in flexible and deformable electronics. Here, we introduce a novel method using nanosilicates to help sinter LM through capillary evaporation, resulting in strong adhesion to substrates. By adjustment of the amount of nanosilicates, flexible EMI shielding yarns are created using dip-coating and curing processes. The sintered LM tightly adhered to the undulating and uneven surfaces of polyurethane (PU) yarns. The as-fabricated ION/LM@PU ("ION" is abbreviation of "ionogel") has strong EMI shielding and low EM-wave reflection due to the high electrical conductivity of the LM layer and good impedance matching of P(AAm-co-AA) ionogel. The addition of an ionogel enhances EM-wave absorption and strengthens interfacial polarization, making it an effective green EMI shielding yarn for reducing secondary reflection pollution. ION/LM@PU exhibited high total electromagnetic interference shielding effectiveness (EMI SET) (∼56 dB), low reflected power coefficient (R) (∼0.153), high impedance matching (|Zin/Z0| ≈ 0.660), high tensile strength (∼23.75 MPa), and high elastic recovery (∼0.92 at 10th stretch-release cycle). The EMI shielding mechanism of ION/LM@PU ± 60° is composed of reflective loss and absorption loss (including multireflective loss, conduction loss, dipole polarization loss, and interfacial polarization loss).

Effect of Composite Scanning Strategy on Forming Quality, Microstructure, and Tensile Properties of Laser Powder Bed Fusion Titanium Alloy

Laser powder bed fusion (LPBF) technology offers significant advantages in manufacturing complex‐shaped titanium alloy components. Traditional scanning strategies, such as zigzag and island scanning, however, often fall short in fabricating parts with variable cross sections. To enhance the forming quality of components featuring combined thin‐walled and bulk structures, a composite scanning strategy is proposed that adapts to the local characteristics of parts. This novel approach is designed to employ both island and zigzag scanning within the same deposition layer, aiming to optimize the balance between porosity and stress distribution. Notably, with a feature transition distance of 4 mm and a scan line offset of 0.67 mm, the specimens achieve a tensile strength of 1311.0 MPa, a yield strength of 1103.0 MPa, and an elongation of 8.8%. This strategy leads to the optimization of defects and a transition in microstructure for combined structural features. These promising outcomes lay the foundation for the intelligent allocation of scanning strategies and the high‐quality formation of complex‐shaped, high‐strength titanium alloy parts.

Investigation of impact of Calotropis procera extract for properties of mild steel in acidic mediums

Mild steel, widely used in gas and oil pipelines, is recognized for its remarkable capacity to absorb both internal and external energy, as well as its high tensile strength. Despite these attributes, the constant exposure to corrosive toxic substances within these pipelines poses a significant challenge. Over time, corrosion weakens the steel’s resilience to impact and increases the likelihood of failure or explosion due to the buildup of fluid pressure. To mitigate this issue, we explored an eco-friendly approach by introducing natural, non-toxic additives derived from the plant Calotropis procera (CP). The goal was to restore some of the steel's lost energy absorption capacity and enhance its resistance to corrosion and fracture.To test the effectiveness of Calotropis procera extract, we conducted weight-loss experiments using API 5L X70 steel in a solution containing 1 mol sulfuric acid and oil. We varied the concentration of CP plant extract in the solution, using 5%, 7%, 10%, and 13% to evaluate its corrosion inhibition properties. Surface examination was carried out using optical microscopy, which confirmed a corrosion inhibition rate of 50% in the CP + H₂SO₄ solution. To further investigate the mechanical performance, we performed Charpy impact tests in the same acidic environment with CP concentrations of 5%, 7%, and 10%. The results revealed that at a 10% concentration of plant extract, the steel exhibited an absorbed impact energy of 278 J, with a corresponding resilience value of 348.325 J/cm². These findings demonstrate the potential of Calotropis procera extract as an effective, sustainable solution for improving the durability of steel used in corrosive environments.

Comparative analysis of armid fiber reinforced polymer for strengthening reinforced concrete beam‐column joints under cyclic loading

AbstractThis research investigates the structural performance and failure mechanisms of beam‐column joints reinforced with aramid fiber‐reinforced polymer to bolster the durability and seismic resilience of concrete structures. It meticulously selects and proportions materials such as ordinary Portland cement Grade 53 cement, fine and coarse aggregates meeting IS: 383–1970 standards, and water conforming to IS: 456–2000 specifications. Tests confirm the high quality of ordinary Portland cement, crucial for optimal beam‐column joint performance, while carbon fiber‐reinforced polymer enhances structural integrity with its lightweight composition and substantial tensile strength (3800 MPa–4200 MPa). Failure analysis reveals that non‐aramid fiber reinforced polymer wrapped beam‐column joint specimens predominantly failed due to concrete crushing, whereas aramid fiber‐reinforced polymer‐wrapped specimens failed due to fracture in the aramid fiber‐reinforced polymer composite, emphasizing stress concentration areas. This study underscores the pivotal role of stress distribution in failure mechanisms and underscores the significance of robust reinforcement design in bolstering structural resilience. These insights advance retrofitting strategies and reinforce techniques aimed at enhancing the longevity and seismic resistance of concrete structures.

Production of a Wood–Plastic Composite with Wastes from Disposable Masks and Corrugated Cardboard: A Sustainable Post-Pandemic Approach

The increasing demand for disposable textile products, personal care items, and electronic commerce has led to a substantial rise in waste generation, particularly from nonwoven fabric masks (wNWFs) and corrugated cardboard (wCC). This study assessed the feasibility of utilizing these waste materials, which were produced in significant amounts during the COVID-19 pandemic, as both a matrix and reinforcement filler in wood–plastic composites (WPCs). The WPC was fabricated using either two extrusion cycles or thermokinetic homogenization, with both processes being followed by hot pressing. The formulations consisted of virgin polypropylene (vPP), wNWF, and wCC in proportions of 45, 45, and 10 wt %, respectively. The results demonstrated that the composites produced via two extrusion cycles exhibited a tensile strength that was 85% higher and three-point flexural strength three times greater than those produced through thermokinetic homogenization. These findings contribute to advancements in scientific and technological knowledge and offer an efficient solution for managing these types of waste, which continue to be generated post-pandemic.

Microstructural, mechanical and wear behaviour of AA7075/ZrSiO4 surface composite developed via multi pass friction stir processing

ABSTRACT The microstructural, mechanical, and wear behaviour of the ZrSiO4-reinforced AA7075 surface composites fabricated through friction stir processing was analysed. The microstructure of the friction stir processed surface composite shows refined grain 52 μm, 20 μm and 5 μm after 1, 2 and 3 FSP pass which also leads to the uniform dispersion of reinforced ZrSiO4 particles in the A7075 surface as revealed by SEM, EDS, and XRD. The microhardness and tensile strength of the FSP surface composite were significantly improved by 35% and 54%, respectively, with the effect of ZrSiO4 particles, after six passes as compared to the substrate material. The slurry abrasive wear resistance of the surface composite after six FSP passes increased to 95% as compared to the A7075 substrate material. Similarly, the slurry erosive wear resistance was improved with increasing slurry rotating speed, but as slurry concentration increased at six passes, the wear rate decreased further due to self-colloids occurring between the slurry particles. Hence, slurry erosive wear resistance was increased by up to 220% as compared to substrate material. Hence, the novel fabrication of friction stir processed surface composite will be very beneficial for aerospace and marine structural components and the fabrication process is very robust and cost-efficient.

Effect of Amorphous Metallic Fibers on Thermal and Mechanical Properties of Lightweight Aggregate Cement Mortars Containing Carbon Nanotubes

Lightweight aggregate concrete can reduce the self-weight of a structure with a low unit weight; however, disadvantages such as reduced strength and brittleness remain. This study evaluated the thermal and mechanical properties of lightweight aggregate cement mortars containing carbon nanotubes (CNTs) and amorphous metallic fibers (AMFs). A thermal property test indicated that the peak temperature of the C1A1 and C1A2 samples using AMFs was approximately 91.5–93.8 °C (approximately 57.2–61.1% higher than the C1A0 sample without AMFs). The time to reach the peak temperature was approximately 15–27 min (21.1–38.0% of that for the C1A0 sample). The 28-day split tensile strength of the sample using 20 kg/m3 of the AMFs was approximately 3.6–3.8 MPa (approximately 46.1–50.0% higher than that of CNT-only samples). The 56-day flexural strength of the C2A2 sample using 0.2% CNTs and 20 kg/m3 AMFs was the highest at approximately 11.2 MPa (approximately 24.4% higher than that of the control sample). The results of this study indicate that using CNTs and AMFs can enhance the strength and reduce the brittleness of lightweight aggregate cement mortar. Furthermore, the performance of the cement mortar is significantly improved when combined with AMFs compared to using CNTs alone.

Investigation of the Seismic Performance of a Multi-Story, Multi-Bay Special Truss Moment Steel Frame with X-Diagonal Shape Memory Alloy Bars

In this work, the seismic response of a multi-story, multi-bay special truss moment frame (STMF) with Ni-Ti shape memory alloys (SMAs) incorporated in the form of X-diagonal braces in the special segment is investigated. The diameter of the SMAs per diagonal in each floor was initially determined, considering the expected ultimate strength of the special segment, developed when the frame reaches its target drift and the desirable collapse mechanism, i.e., the formation of plastic hinges, according to the performance-based plastic design procedure. To further investigate the response of the structure with the SMAs incorporated, half the calculated SMA diameters were introduced. Continuing, three more cases were investigated: the mean value of the SMA diameter was introduced at each floor (case DC1), half the SMA diameter of case DC1 (case DC2), and twice the SMA diameter of case DC1 (case CD3). Dynamic time history analyses under seven benchmark earthquakes were conducted using commercial nonlinear Finite Element software (SeismoStruct 2024). Results were presented in the form of top-displacement time histories, the SMAs force–displacement curves, and maximum inter-story drifts, calculating also maximum SMA displacements. The analysis outcomes highlight the potential of the SMAs to be considered as a novel material in the seismic retrofit of steel structures. Both design approaches presented exhibit a certain amount of effectiveness, depending on the distribution, with the placement of the SMA bars and the seismic excitation considered. Further research is suggested to fully understand the capabilities of the use of SMAs as dissipation devices in steel structures.

Correlating FDM printing parameters with mechanical properties and surface quality of PLA printouts

Abstract This study explores the correlation between four critical Fused Deposition Modeling (FDM) parameters—extrusion temperature, layer height, print speed, and infill density—and the mechanical properties and surface quality of PLA (Polylactic Acid) printouts. The mechanical properties, including Young’s modulus, tensile strength, and bending strength, were evaluated alongside surface roughness and dimensional accuracy. The results indicate that extrusion temperatures between 200°C and 220°C optimize mechanical performance, enhancing tensile strength and bending strength, while smaller layer heights (0.1 mm) improve surface smoothness but increase print time. Moderate print speeds (around 60 mm/s) offer the best balance between strength and efficiency, while higher infill densities (above 80%) enhance mechanical properties, increasing both tensile and bending strength by up to 25%. These findings provide key insights into optimizing FDM printing parameters to achieve improved structural integrity and aesthetic quality in PLA prints.

A novel thermoplastic material: Pre‐polymerized PMMA liquid resin and continuous glass fiber‐reinforced composite initiated by benzoyl peroxide/N,N‐dimethylaniline

AbstractThermoplastic PMMA was rarely exploited in continuous fiber‐reinforced composites due to its viscous high‐temperature molten fluid as well as pessimistic wettability into fiber fabric. Redox‐active polymerization is a green route to develop a new liquid PMMA resin at room temperature to provide an in situ curing with the advantages of energy saving and consumption reduction. In this paper, BPO/DMA was adopted as a redox initiator pair, and the effect of MMA:BPO:DMA ratio on curing time, Mn, Tg, and mechanical properties of PMMA were systematically studied. When the ratio of MMA:BPO:DMA is 200:1.2:1, PMMA‐200 achieved optimistic mechanical properties at 20°C (tensile strength, 64.7 MPa; tensile modulus, 3352 MPa; bending strength, 125.3 MPa; bending modulus, 3023 MPa). Moreover, the mechanical properties were further improved at low temperatures. The maximum tensile strength and tensile modulus were up to 97.43 and 4297 MPa (−40°C) respectively. The tensile strength (0°, 1103 MPa; 90°, 52.3 MPa) and tensile modulus (0°, 47.5 GPa; 90°, 14.2 GPa) of glass‐fiber‐reinforced PMMA composite at 20°C were found to be comparable with epoxy resin‐based composites and even higher at lower temperature. In summary, redox‐initiated PMMA and its fiber‐reinforced composites are promising thermoplastic materials as new lightweight alternatives.Highlights Preparation method of PMMA resin and glass fiber composite. Research on the mechanical properties, molecular weight, glass transition temperature, curing time, etc. of PMMA resin. Testing of mechanical properties of PMMA glass fiber composites at room temperature and low temperature. Current applications and prospects of PMMA glass fiber composites.