B4C Nanoparticles Research Articles

Effect of B4C nanoparticles addition on the refinement of Fe-rich phase in ZL108 alloy

Refining effect of B4C nanoparticles in ZL108 alloy on Fe-rich phase was studied in this work. It was observed that B4C nanoparticles apparently refines the size of the Fe-rich phases and partially transforms Fe-rich phases morphology from hollow polyhedron to petal-like shape. The DSC results show that B4C nanoparticles does not affect the initial nucleation temperature of the Fe-rich phase. However, the addition of B4C nanoparticles to ZL108 alloy inhibits the growth of Fe-rich phase. The TEM results confirm that the addition of B4C nanoparticles alters the lattice parameter of Fe-rich phase due to incorporation of C atoms, thereby suppressing the growth of the Fe-rich phase and ultimately leading to its refinement. From the perspective of fracture behavior, the addition of B4C nanoparticles remarkably reduces the stress concentration of Fe-rich phase, and the elongation of the alloy increases by 25.3%. These findings provide a new perspective for further research and development to refine Fe-rich phase.

Effect of mechanical milling time on powder characteristic, microstructure, and mechanical properties of AA2024/B4C/GNPs hybrid nanocomposites

In this study, hybrid nanocomposites consisting of an AA2024 matrix reinforced with 1 wt% B4C nanoparticles and 1 wt% GNPs were produced using a powder metallurgy method assisted by mechanical milling. This study aimed to systematically investigate the effect of grinding time on powder characteristics (particle size, microhardness, and morphology) as well as microstructure, densification, and mechanical performance to optimize processing conditions for superior material properties. Microstructural characterization of powders and bulk samples were carried out using a SEM device equipped with EDS. The results indicate that with increasing milling time, the particle size significantly decreased, while the particle hardness increased substantially. Additionally, the sample milled for 8 h achieved the highest relative density among the hybrid nanocomposites, reaching a value of 95.3 %. Mechanical tests revealed that after 8 h of milling, the hardness and tensile strength reached peak values of 164 HB and 314 MPa, corresponding to increases of 56 % in hardness and 43 % in tensile strength compared to the unreinforced alloy. The analysis results confirm that the optimal properties were obtained after 8 h under all conditions.

Transparent self-cleaning coating prepared from SiO2/B4C and SiO2/B4C/TiO2 for the solar cell

Transparent self-cleaning coatings based on photocatalytic activity have attracted great attention in recent years owing to their promising applications in many fields, such as solar cell cover glass. This study reports a simple method to prepare transparent self-cleaning silicon dioxide (SiO2) coatings filled by boron carbide (B4C) and titanium dioxide (TiO2) nanoparticles. A sol-gel technique was used to synthesize a SiO2 solution containing B4C and TiO2 nanoparticles, and a dip-coating technique was followed to coat the composite solution on glass slides. The SiO2 coating was successfully obtained in the presence of both semiconductor nanoparticles as confirmed by FTIR and XRD measurements. Both the photocatalytic activity and self-cleaning property of the composite coatings were evaluated by photocatalytic degradation of a model dye, methylene blue, under visible light irradiation. The SiO2 coating containing both B4C and TiO2 nanoparticles exhibited an improved photocatalytic activity compared to the SiO2 coating including only B4C. In particular, a 46% degradation rate of the model dye methylene blue was achieved for the SiO2 coating containing 15 wt% B4C and 5 wt% TiO2 nanoparticles. Highly transparent composite coatings on glass slides were prepared. The SiO2 coating containing both B4C and TiO2 nanoparticles was found to exhibit ~8% reduction in the optical transmission of the glass slide and ~1% reduction in the efficiency of a solar cell containing the coated glass slide. These findings demonstrated that the SiO2 composite coatings have potential for self-cleaning applications in removing contaminants from the glass cover of the solar cell under visible light irradiation.Graphical

The Impact of nanoparticles (B4C-Al2O3) on mechanical, wear, fracture behavior and machining properties of formwork grade Al7075 composites

This study explores how ageing temperature and the volume percentage of Al2O3+B4C nanoparticles influence the machinability and hardness of stir-cast Al-7075 Metal Matrix Composite (MMC). Using liquid metallurgy techniques, hybrid materials were created by reinforcing Al7075 metal matrix with varying weight percentages of nanosized B4C (1.5%, 3%, and 4.5%) and Al2O3 (1%, 1.5%, and 2%). After fabrication, the samples were subjected to five-hour ageing process at temperatures of 100, 120, and 140 degrees Celsius, followed by cooling to ambient temperature (27 degrees Celsius). Hybrid nano composites that had been heat treated were tested for wear, tensile strength, and hardness. Results shows that, the addition of nanoparticles and heat treatment considerably improves the tensile strength, hardness, and wear resistance of hybrid composites by 3%, 17%, and 10%, respectively, for samples reinforced with 4.5% B4C + 2% Al2O3. SEM analysis was used to investigate the type of wear and the tensile fracture mode of nano composite samples by analyzing the wornout surface and the surface where tensile fracture occurred. Machinability was assessed using L27 orthogonal array tests, focusing on three key process parameters: feed rate (0.1 mm/min), depth of cut (0.2 mm/min), and spindle speed (1000 rpm). Outcomes show that, increasing the wt. % of nano-Al2O3/B4C leads to higher machining force and surface roughness (Ra) of MMCs. Conversely, higher ageing temperatures result in decreased machining force and surface roughness. Optimal surface roughness and machining force were achieved with 1% Al2O3 + 1.5% B4C and an ageing temperature of 140°C. These findings offer valuable insights into the ease of machining of composite metal alloys, emphasizing the importance of parameter selection and optimization for desired machining outcomes.

Thermophysical properties and enhancement behavior of novel B4C-nanoadditive RT35HC nanocomposite phase change materials: Structural, morphological, thermal energy storage and thermal stability

This study aims to enhancement the thermal conductivity of RT35HC, as a commercial paraffin, by integrating boron carbide (B4C) nanoparticles for the first time, thereby producing B4C-nanoadditive nanocomposite PCMs. The B4C nanoparticles were reinforcement to RT35HC at mass fraction percentages (wt.%) of 0.5, 1, 1.5 and 2 by melting and physical mixing method. The structural and morphological characteristics of both pure and nanocomposite PCMs were examined using XRD, FT-IR, FE-SEM, and EDX. Thermal properties were investigated through DSC, TGA/DTA, and thermal conductivity measurements using the KD2-Pro device. The Gaussian process regression (GPR) model was used to analyze the Cp values in relation to temperature and additive ratio. Structural and morphological analysis results indicated a homogeneous distribution of nanoparticles within the PCM matrix, without any significant chemical or physical alterations. The introduction of B4C-nanoadditive did not markedly affect the melting and solidification temperatures. However, melting and solidification enthalpies decreased proportionally with increased nanoadditive ratios, with the greatest reductions being 7.44 % and 5.74 % at a 2 wt% nanoaddition rate, respectively. As the nanoadditive ratio increased, the thermal conductivity (k) and specific heat capacity (Cp) of RT35HC in both solid and liquid-phases enhanced significantly. Specifically, solid-phase (25 °C) k values increased by 67.51 % from 0.197 to 0.33, and liquid-phase (50 °C) k values by 15.29 % from 0.170 to 0.196. The highest Cp values in the solid and liquid-phases were measured as 3.01 and 2.49, respectively, in the nanocomposite with a high nanoadditive ratio. The GPR method yielded a success rate of 0.9015. Additionally, the nanocomposites exhibited enhanced thermal stability and higher thermal decomposition temperatures. Based on these characterizations, the fabricated B4C-nanoadditive nanocomposite PCMs show promise for application in TES and TM systems.

Characterization of Al-Si Alloy Reinforced with B4C and TiO2 Nanoparticles

Characterization of Al-Si Alloy Reinforced with B4C and TiO2 Nanoparticles

Synthesis and Characterization of B4C-Based Multifunctional Nanoparticles for Boron Neutron Capture Therapy Applications

Nanoparticles composed of inorganic boron-containing compounds represent a promising candidate as 10B carriers for BNCT. This study focuses on the synthesis, characterization, and assessment of the biological activity of composite nanomaterials based on boron carbide (B4C). Boron carbide is a compelling alternative to borated molecules due to its high volumetric B content, prolonged retention in biological systems, and low toxicity. These attributes lead to a substantial accumulation of B in tissues, eliminating the need for isotopically enriched compounds. In our approach, B4C nanoparticles were included in composite nanostructures with ultrasmall superparamagnetic nanoparticles (SPIONs), coated with poly (acrylic acid), and further functionalized with the fluorophore DiI. The successful internalization of these nanoparticles in HeLa cells was confirmed, and a significant uptake of 10B was observed. Micro-distribution studies were conducted using intracellular neutron autoradiography, providing valuable insights into the spatial distribution of the nanoparticles within cells. These findings strongly indicate that the developed nanomaterials hold significant promise as effective carriers for 10B in BNCT, showcasing their potential for advancing cancer treatment methodologies.

Synergistic strategy for enhancing the thermoelectric properties of Bi0.5Sb1.5Te3 with excess Te through low-temperature liquid phase sintering method

The thermoelectric properties of Bi0.5Sb1.5Te3 synthesized through the low-temperature liquid phase sintering (LPS) method can be significantly improved by employing a synergistic approach. During the heat treatment, excess Te undergoes self-swelling under optimal sintering pressure, facilitating the slip of matrix grains perpendicular to the applied pressure and subsequent recrystallization, leading to enhanced electrical properties. Building upon this basis, the heightened Seebeck coefficient and power factor of the thermoelectric matrix stem from the incorporation of 0.6 vol% B4C nanoparticles. Simultaneously, lattice thermal conductivity experiences notable suppression due to enhanced phonon scattering induced by additional interfaces, defects, and second-phase. Lastly, a markedly improved maximum ZT value of 1.30 at 333 K is achieved when the volume percentage of B4C nanoparticles is 0.6 vol%, representing a remarkable 23% enhancement compared to the untreated sample. These results indicate that the LPS method, coupled with the enhanced second nanophase scattering mechanism, is beneficial to enhancing the thermoelectric properties of Bi2Te3-based materials.

Study of basalt/hemp fibers reinforced B4C nanoparticles influenced hybrid epoxy composite: a novel approach for optical fiber insulation

Study of basalt/hemp fibers reinforced B4C nanoparticles influenced hybrid epoxy composite: a novel approach for optical fiber insulation

Interface‐Enhanced High‐Temperature Thermoelectricity in Cu1.99Se/B4C Composites with Synergistically Improved Mechanical Strength

AbstractDegenerate semiconductors usually demonstrate a metallic‐like conduction behavior, showing limited carrier mobility at high temperatures. Herein, by incorporating B4C nanoparticles into the Cu1.99Se system, an unusual switch from the “degenerate” to “non‐degenerate” semiconducting behavior is revealed as a result of the engineered interfaces. Heterogeneous interfaces and disordered Cu2Se amorphous phases are introduced in the Cu1.99Se/B4C composites, which generate a trapping effect against the mobile Cu ions, leading to a distinctive “hump” signature for electrical conductivity. Benefiting from this rare high‐temperature thermoelectric response, a high power factor is obtained due to reduced carrier concentration and enhanced mobility, and low lattice thermal conductivity is retained because of relatively stronger anharmonic lattice vibrations. Consequently, the Cu1.99Se + 0.9 vol.% B4C sample at least achieves a maximum thermoelectric figure of merit (ZT) of 2.6 at 1025 K with synergistically enhanced mechanical robustness. The present interface engineering strategy may be applicable to other thermoelectric materials with ionic migration characteristics.

Wear Characteristics of (Al/B4C and Al/TiC) Nanocomposites Synthesized via Powder Metallurgy Method

Objective: The aim of the present work is to study the microstructure, wear behavior, physical properties, and micro-hardness of the aluminum matrix AA6061 reinforced with TiC and B4C nanoparticles with different concentrations of 2.5, 5, 7.5, 10, and 12.5 wt.%. Methodology: Al/B4C and Al/TiC nanocomposites were fabricated with a powder metallurgy route. A dry sliding wear test was performed with a pin-on-disc machine. The wear test was performed at the applied loads of 3, 6, 9, 12, and 15 N at a constant time for about 10 min. The microstructural analysis of the fabricated nanocomposites was examined via field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analysis. The obtained data: The results of this work show that increasing the applied load leads to a decrease in the wear rate of the aluminum matrix and its nanocomposites. The wear rate of the aluminum matrix without any additives is about 7.25 × 10−7 (g/cm), while for Al/TiC and Al/B4C, it is 5.1 × 10−7 (g/cm) and 4.21 × 10−7 (g/cm), respectively. An increment in B4C percent increases the actual density, while an increment in TiC percent minimizes the actual density at 2.90 g/cm3 and 2.51 g/cm3, respectively. An increment in B4C percent decreases by 4.61%, while the porosity slightly increases with increases in TiC percent of 6.2%. Finally, the micro-hardness for Al/B4C is about 92 (HRC), and for Al/TiC, it is about 87.4 (HRC). Originality: In the present work, nanocomposites were fabricated using a powder metallurgy route. Fabricated nanocomposites are important in engineering industries owing to their excellent wear resistance, low thermal distortion, and light weight compared with other nanocomposites. On the other hand, Al/B4C and Al/TiC nanocomposites fabricated with a powder metallurgy route have not previously been investigated in a comparative study. Therefore, an investigation into these nanocomposites was performed.

New insights into the microstructural evolution and properties of (TiB+TiC)/Ti–6Al–4V composite via laser directed energy deposition using B4C nanoparticles

Additive manufacturing(AM) holds enormous application potential in the aerospace industry for fabricating (TiB + TiC)/Ti composite materials (TMC). However, TMCs produced using AM still face challenges related to low ductility. This study reports on the microstructure and mechanical properties of TMCs prepared using B4C nanoparticles through via coincident wire powder laser-directed energy deposition (CWPLDED). The TMC matrix grain size is significantly refined, attributed to the favorable nucleation of the dispersed TiB and TiC during α-Ti solid-state transformation. The maximum ultimate tensile strength of the TMC is 1294.9 ± 7.6 MPa, with an elongation of 4.4 ± 0.26 %, and the dispersed reinforcing phases enhance the strength and ductility of the TMC. This work offers a novel approach for utilizing CWPLDED to fabricate (TiB + TiC)/Ti64 composites with exceptional comprehensive performance.

Ferroconcrete-inspired construction of wearable composites with a natural leather matrix for excellent neutron-shielding performance

In various sectors, including medical radiotherapy, aerospace exploration, and nuclear energy, the necessity for advanced neutron-shielding materials has escalated. However, these materials often exhibit poor mechanical performance and limited adaptability. To address these shortcomings, this study introduces a novel approach inspired by ferroconcrete construction to develop wearable neutron-shielding materials. This method utilizes the collagen fiber-supported framework present in natural leather, serving as a flexible skeleton, and employs functionalized B4C nanoparticles and paraffin as fillers. The interconnected voids and the unique hierarchical structure of the collagen fibers work synergistically to enable uniform dispersion of B4C nanoparticles, thus enriching the resultant composites with superior neutron-shielding performance. The composite material prepared through this method exhibits a remarkable neutron-shielding effectiveness of 96.93 % and a high linear attenuation coefficient of 17.46 cm−1, outperforming other shielding materials. Additionally, the three-dimensional (3D) woven network of the collagen fiber-supported framework offers impressive mechanical properties, including a tensile strength of 28.59 MPa. This innovative design strategy for creating new wearable neutron-shielding materials paves the way for manufacturing advanced neutron-protective clothing and propels a new structural design with elevated shielding and mechanical performance.

Synthesis and Characterization of Boron Carbide Nanoparticles as Potential Boron-Rich Therapeutic Carriers.

Boron carbide is one of the hardest materials in the world which can be synthesized by various methods. The most common one is a carbothermic or magnesiothermic reduction of B2O3 performed at high temperatures, where the obtained powder still requires grinding and purification. The goal of this research is to present the possibility of synthesizing B4C nanoparticles from elements via vapor deposition and modifying the morphology of the obtained powders, particularly those synthesized at high temperatures. B4C nanoparticles were synthesized in the process of direct synthesis from boron and carbon powders heated at the temperature of 1650 °C for 2 h under argon and characterized by using scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction analysis, and dynamic light scattering measurements. The physicochemical characteristics of B4C nanoparticles were determined, including the diffusion coefficients, hydrodynamic diameter, electrophoretic mobilities, and zeta potentials. An evaluation of the obtained B4C nanoparticles was performed on several human and mouse cell lines, showing the relation between the cytotoxicity effect and the size of the synthesized nanoparticles. Assessing the suitability of the synthesized B4C for further modifications in terms of its applicability in boron neutron capture therapy was the overarching goal of this research.

Ultrasonic-assisted connection of Cu/Cu structure using Sn58Bi solder enhanced by B4C nanoparticles

In order to enhance the joint performance, the Cu/Sn58Bi-0.6B4C/Cu 3D structure was obtained by ultrasonic-assisted connection. The influence of ultrasound on the solder and its wettability, as well as the microstructure, interfacial IMC structure, and mechanical properties, was investigated. It is indicated that ultrasonic cavitation improves the crystal structure of the solder alloy by refining grain size and making the microstructure more uniform. The ultrasound also changes the preferred orientation of β-Sn and Bi phases, and increases the low-angle grain boundaries and local orientation differences for improved alloy strength. Additionally, the ultrasound promotes the molten solder spreading on the Cu substrate. The microstructure of the filler metal layer is improved by ultrasonic, and the Cu6Sn5 compounds floating in the solder matrix act as the strengthening phase. Cavitation bubbles erosion increases the contact area between the solder and Cu substrate. The audiogenic high temperature reduces the IMC thickness difference at both ends of the joint caused by the temperature gradient. Besides, the grain size in the solder matrix and interfacial IMC is refined with increased supercooling. The ultrasound strengthens joint shear strength significantly and improves the potential path for crack propagation. The appearance of dimples in the fracture alters its mode from being typically brittle to a mixed ductile and brittle fracture. The above enhancement will be further improved with the appropriate extension of ultrasonic time. We hope to strengthen joint performance by ultrasound, and provide reference for future research and application combining soldering with ultrasonic technology.

The Effect of Hybrid B4C and Si3N4 Nanoparticles on the Mechanical and Physical Properties of Copper Nanocomposites

This study investigated the effects of reinforcing pure copper with hybrid B4C and Si3N4 nanoparticles on the mechanical and physical properties of the nanocomposite matrix. The composite matrix was prepared using the powder metallurgy (PM) method, allowing uniform nanoparticle dispersion within the copper matrix. The PM method was a practical approach for achieving a homogeneous and good dispersion of the reinforcing particles in the matrix while controlling the porosity and improving the microstructure of the fabricated composite matrix. The addition of B4C and Si3N4 are both very hard and dense materials. When added to a material, they can fill voids and reduce porosity. This can lead to significant improvements in the material’s mechanical properties. The study found that adding hybrid B4C and Si3N4 nanoparticles enhanced the microhardness and mechanical properties of the nanocomposites. The improvements in the mechanical and physical properties of such composites containing 5% B4C were 21.6% and 18.4% higher than the copper base alloy. The findings suggest that including ceramic particles is a viable strategy for enhancing the mechanical characteristics of copper in its pure form. For example, adding 5% B4C particles to copper resulted in a 23% increase in Young’s modulus of the material while reducing electrical conductivity by 4.6%. On the other hand, the hybrid composite Cu/5%B4C + 2.5%Si3N4 showed a 32% improvement in Young’s modulus and 71% in the microhardness value compared to the base metal. This makes it a promising option for various engineering applications, such as high-performance electrical contacts and bearings.

Investigation of the mechanical, corrosion, and tribological characteristics of AZ61 Mg with boron carbide nano particles via the stir casting route

Abstract Magnesium composites are innovative, compact, and distinctive materials. Because of their low density, magnesium composites are suitable for applications in the automobile, aviation, semiconductor, and pharmaceutical sectors. To enhance the mechanical wear and corrosion behavior of theAZ61 Mg alloy, different weight percentages of nano-B4C reinforcements (2.5, 5, 7.5, and 10wt%) were strengthened with magnesium matrix. Fabrication of magnesium composites was achieved through the stir casting method. The as-cast specimens were subjected to microstructural analysis, which showed that the B4C nanoparticles were dispersed uniformly, well bonded to the matrix, and had a minimal level of porosity. This shows that the inclusion of B4C nanoparticles has aninsignificanteffect on the microstructure of the as-cast material. The material’s tensile strength, compressive strength, hardness, corrosion resistance, and wear resistance were all greatly increased by the Mg17Al12 phase’s fracture and dispersion. Scanning electron microscopy was utilized to inspect the surfaces of AZ61/B4C nanocomposites and witnessed the uniform dispersal of reinforcement within the matrix.The maximum value for mechanical properties was obtained for AZ61/7.5wt%B4C nanocomposite and the lowest value was found to be the corrosion test. These results show that the AZ61/7.5wt%B4C nanocomposite is a superior material for aerospace and automotive engineering components where high compressive strength, corrosion resistance, and wear resistance are required.

Enhancement of saltwater ageing behavior of nanocomposites and lap joints with boron nanoparticles

The presented research aims to enhance the ageing performance of nanocomposites and bonded joints in the saltwater medium with boron nanoparticle doping. Epoxy nanocomposites and bonded aluminum 2024-T3 joints doped with 2 wt% silane-functionalized boron carbide (B4C) and boron nitride (BN) nanoparticles and undoped were produced for that purpose. The produced samples were immersed in a saltwater (10% NaCl) solution at 40 °C for 480, 960 and 1440 h. By performing the weight change test, Fourier transform infrared (FT-IR) spectroscopy, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), tensile test and scanning electron microscope (SEM), the research aimed to comprehensively assess the changes in the properties of nanocomposites and lap joints after exposure to saltwater ageing, shedding light on the effectiveness of boron nanoparticle doping in improving their performance in saltwater environments. The result showed that thanks to the anti-plasticisation behaviour of nanoparticles, 18.4% and 19.6% higher Tg values were obtained in B4C and BN-doped nanocomposites after 1440 h of ageing, respectively. Similarly, the static tensile strength of the undoped composite decreased by 22%, while B4C and BN-doped nanocomposites decreased by 15% and 14%, respectively, at the end of ageing. After 1440 h, the storage modulus of undoped, B4C and BN-doped nanocomposites decreased by 24.2%, 15.3% and 11.9%, respectively. It was found that B4C and BN-doped bonded joints performed superior mechanical properties compared to their undoped counterparts. The joints doped with B4C and BN nanoparticles carried 50% and 52% higher loads than the undoped joint.

Residual stress effects on toughening of ultrafine-grained B4C-SiC ceramics

The attainment of both enhanced toughness and super hardness is crucial for B4C ceramics. Refining grains to the nanoscale is known to be an effective strategy to address the above issue, but remains a great challenge. In this work, B4C and SiC nanoparticles were synthesized and used for the preparation of ultrafine-grained B4C-SiC ceramics. The grain size effect on the mechanical properties of composites was systematically investigated. It is found that, contrary to the conventional view that there is almost no residual thermal stress in the B4C-SiC interface, residual stress arises as B4C grains reach a nanostructured state, and the toughness can be considerably improved to 5.13 MPa m1/2. The B4C-SiC composite also demonstrates excellent hardness of 36.6 GPa, even superior to that of monolithic B4C ceramics. This study has important implications for the development of toughening mechanisms for B4C-SiC ceramics and presents a new strategy for producing high-performance ceramics.

Refinement behaviour of microstructure in in-situ synthesised (TiB+TiC)/Ti6Al4V composites by laser melting deposition

Laser melting deposition (LMD) was used to stimulate the columnar to equiaxed transition (CET) of Ti6Al4V grains by adding a few of nano-B4C particles. The results showed that the grains were gradually refined with the increase of B4C content. When the B4C content is 3 wt-%, the titanium matrix composite material of B4C and Ti6Al4V reached CET. Ti6Al4V and B4C happened in-situ reaction to form TiB and TiC reinforcements at high temperature, which not only precipitate at grain boundaries to limit grain growth but also act as nucleation to accelerate the non-spontaneous nucleation of β grains to achieve fine grain strengthening. It reveals the epitaxial growth mechanism of β grains at the deposition bottom, the transition pattern and CET mechanism of the interface structure in successive deposition layers.