Boron Carbide Content Research Articles

Experimental, simulation, and theoretical investigations of gamma and neutron shielding characteristics for reinforced with boron carbide and titanium oxide composites

This study investigates the radiation shielding properties of composites containing polyester resin, boron carbide and titanium oxide in varying proportions. The radiation transmittance of the produced composites was measured using radioactive sources 241Am, 137Cs, 133Ba, 60Co, and 22Na across a photon energy range of 59.5 keV–1332.5 keV. To analyze radiation permeability, experimental geometry was simulated using Monte Carlo-based computer codes Monte Carlo N-Particle (MCNP), Particle and Heavy Ion Transport code System (PHITS) and FLUktuierende KAskade or Fluctuating Cascade (FLUKA), and the experimental data were compared with simulation results and theoretical data obtained from WINXCOM. The findings demonstrated a high degree of consistency between experimental, simulation, and theoretical results. Notably, the BCTiO50 sample, which included a 50% addition of TiO2, emerged as the most effective in photon radiation shielding. In addition to gamma shielding, the neutron shielding properties of the produced composites were evaluated using the FLUKA code, revealing that the BCTiO0 sample, with the highest percentage of boron, provided the best neutron shielding. This analysis included composites with decreasing boron carbide content by 10%, 20%, 30%, 40%, and 50% by weight, each replaced with titanium oxide, showcasing the potential applications of these polymer composites in radiation shielding.

The Microstructure, Mechanical, and Friction-Wear Properties of Boron Carbide-Based Composites with TiB2 and SiC Formed In Situ by Reactive Spark Plasma Sintering.

The paper presents the influence of the temperature of the sintering process on the microstructure and selected properties of boron carbide/TiB2/SiC composites obtained in situ by spark plasma sintering (SPS). The homogeneous mixture of boron carbide and 5% vol. Ti5Si3 micropowders were used as the initial material. Spark plasma sintering was conducted at 1700 °C, 1800 °C, and 1900 °C for 10 min after the initial pressing at 35 MPa. The heating and cooling rate was 200 °C/min. The obtained boron carbide composites were subjected to density measurement, an analysis of the chemical and phase composition, microstructure examination, and dry friction-wear tests in ball-on-disc geometry using WC as a counterpart material. The phase compositions of the produced composites differed from the composition of the initial powder mixture. Instead of titanium silicide, two new phases appeared: TiB2 and SiC. The complete disappearance of Ti5Si3 was accompanied by a decrease in the boron carbide content of the stoichiometry formula B13C2 and an increase in the content of TiB2, while the SiC content was almost constant. The relative density of the obtained boron carbide composites, as well as their hardness and resistance to wear, increased with the sintering temperature and TiB2 content. Unfortunately, the reactions occurring during sintering did not allow us to obtain composites with high density and hardness. The relative density was 76-85.2% of the theoretical one, while the Vickers hardness was in the range of 4-12 GPa. The mechanism wear of boron carbide composites tested in friction contact with WC was abrasive. The volumetric wear rate (Wv) of composites decreased with increasing sintering temperature and TiB2 content. The average value of coefficient of friction (CoF) was in the range of 0.54-0.61, i.e., it did not differ significantly from the value for B4C sinters.

Development and evaluation of boron carbide-modified unsaturated polyester resin for use as neutron radiation Protection

Neutrons are electrically neutral particles that can penetrate through various materials and interact with atomic nuclei. Neutrons can emit radiation with varying degrees of energy, which can be harmful to both living organisms and the environment. The objective of this study is to evaluate the thermal neutron (0.025 eV) shielding properties of unsaturated polyester resin with boron carbide content ranging from 0 to 20 wt% for use as neutron shielding materials. The FLUKA Monte Carlo simulation was utilized to evaluate the interactions between thermal neutrons and materials with a thickness of 5 cm. The total cross-section, mean free path, and half-value thickness were calculated to assess the shielding properties of materials. The results indicated that as the boron carbide content increased, the total cross-section increased while the mean free path and half-value thickness decreased. In addition, the polyester resin with 20 wt% of boron carbide exhibited the best properties for shielding thermal neutrons. Thus, this study suggests that unsaturated polyester resin containing boron carbide can be used as an effective material for shielding thermal neutrons.

High Temperature Flexural Strength, Microstructure, and Phase Evolution of Quartz Fiber/Boron Phenolic Resin Ceramizable Composite Modified with W and B4C

In order to investigate the effect of refractory metal on the high temperature properties of phenolic resin matrix composites, modified quartz fiber reinforced ceramizable composites were prepared by a molding process with a refractory component, tungsten, as the functional component and boron carbide as the ceramic forming agent. The effects of the tungsten and the boron carbide on the heat resistance of the composite were investigated. The results showed that the introduced refractory metal tungsten and the boron carbide can react to form tungsten borides and tungsten carbides at high temperature, and form a ceramic layer on the surface of the composite, which can fill the defects caused by pyrolysis of matrix and improve the high temperature performance of the composite. When the content of boron carbide was 10 wt% and the content of tungsten powder was 30 wt%, the flexural strength of the composite before and after heat treatment at 1200 °C were increased by 54.6% and 30.2% respectively compared with that without filler.

Investigation on the impact of B4C content in AA5052 based metal matrix composites on the mechanical properties of welded joints

In this research, the tungsten inert gas welding was used to join together metal matrix composites (MMCs) reinforced in different percentages with B4C. The welding settings were maintained at a constant value for all specimen situations. Thermal ageing was used to achieve maximum age-hardening in the welded composites. Misorientation and energy storage are the microscopic features of aged composites that distinguish them from composites that have not been aged. Tensile strength and hardness both increased with increasing B4C concentration, but at opposite rates, suggesting that hardness resulted from energy storage while tensile strength resulted from misorientation. Age hardening as measured by electron backscatter diffraction (EBSD) occurs due to a active recovery of the weld metal (WM) region following a reorganization in displacement structures caused by the precipitation of magnesium silicate or an increase in boron carbide content. The healing process is primarily driven by the action of precipitation strengthening, rather than the impact of obliteration of displacements, as evidenced by the correlation between tensile strength and reduction in misorientation. Adding B4C to aluminium metal matrix composites before welding causes the structural changes that need to be characterized. The welding process's structural changes are analysed, and connections are made to the welded junctions' mechanical behaviour. The study's findings suggest that the microstructure's misorientation distribution is as crucial as the average amount of misorientation in determining a material's strength.

Structure and Properties of Composite Coatings Cold Sprayed from Powder Mixtures of Aluminum and Boron Carbide

In the present work, an experimental study of the effect of aluminum and boron carbide powder mixture composition on the microstructure and basic properties of the cold sprayed coatings was carried out for the first time. A series of coatings deposited on stainless steel substrates was obtained. The microstructure of the deposited coatings was analyzed by scanning electron microscopy and X-ray diffraction analysis. The microhardness and bonding strength of the coatings were measured. It was shown that an increase from 0 to 72 vol.% in the boron carbide content in the powder mixture leads to an increase in its content from 0 to 15-17 vol.% in the coating, its microhardness – from 46.3 to 72.4 HV0.3, and bonding strength – from 17.4 to 61.4 MPa. The obtained results open up broad prospects for the application of the cold spray method to deposition of functional coatings, which are highly demanded in the nuclear industry.

Electrical, thermal, and mechanical properties of porous silicon carbide ceramics with a boron carbide additive

AbstractThe effects of the boron carbide (B4C) content and sintering atmosphere on the electrical, thermal, and mechanical properties of porous silicon carbide (SiC) ceramics were investigated in the porosity range of 58.3%–70.3%. The electrical resistivities of the nitrogen‐sintered porous SiC ceramics (∼10–1 Ω·cm) were two orders of magnitude lower than those of argon‐sintered porous SiC ceramics (∼101 Ω·cm). Both the thermal conductivities (3.3–19.8 W·m–1·K–1) and flexural strengths (8.1–32.9 MPa) of the argon‐ and nitrogen‐sintered porous SiC ceramics increased as the B4C content increased, owing to the decreased porosity and increased necking area between SiC grains. The electrical resistivity of the porous SiC ceramics was primarily controlled by the sintering atmosphere owing to the N‐doping from the nitrogen atmosphere, and secondarily by the B4C content, owing to the B‐doping from the B4C. In contrast, the thermal conductivity and flexural strength were dependent on both the porosity and necking area, as influenced by both the sintering atmosphere and B4C content. These results suggest that it is possible to decouple the electrical resistivity from the thermal conductivity by judicious selection of the B4C content and sintering atmosphere.

Influence of boron carbide content on dry sliding wear performances of AZ91D magnesium alloy

In this study, AZ91 magnesium alloy based metal matrix composites are made-up of bottom pouring stir casting with 0 wt.%, 1.5 wt.% and 3 wt.% boron carbide (B4C) particles reinforcements. The influence of hard reinforcements on mechanical properties such as hardness and tensile strength has been investigated for the casted composites samples. It was found that by adding 1.5 wt. % and 3 wt.% B4C particles, the Rockwell hardness value of 3.2% and 4.6%, Ultimate Tensile Strength (UTS) values of 15.5% and 26.3% of the composites increased respectively. The influence of B4C contents on AZ91D mg alloy wear study was carried out using pin on disc apparatus. Also, the effect of applied load (5N, 10N, and 20N) on wear properties was investigated. The results of the dry sliding wear tests show that AZ91D- B4C magnesium composite has less wear loss than the unreinforced AZ91D magnesium alloy. X-ray diffraction (XRD) analysis were performed for finding the various compounds such as MgO, B4C and Mg17Al12 present in the developed composites. Further, scanning electron microscopy (SEM) analysis were performed on the worn-out pin surfaces to investigate the wear pattern. These findings indicate that the addition of B4C content improved mechanical characteristics and wear resistance, which may also be used in the automotive and aerospace industries.

Properties of coatings obtained from a mechanically treated boron-containing mixture of powders by cold spray method

For composite coatings obtained by cold spraying from powder mixtures of compositions Al + 50 wt.% B and Al + 50 wt.% B4C prepared in a V-shaped mixer and by mechanical processing in a planetary mill, a comparison of effect of these methods for preparing mixtures on the boron (boron carbide) content in the coating was carried out. It is shown that, regardless of the method of preparation, the boron and/or boron carbide contents in the coating have close values, which is confirmed by the results of X-ray phase analysis and visual processing of images of the coating structure. Keywords: cold spray, composite material, high-energy planetary mill, aluminum, boron carbide, X-ray phase analysis.

Свойства покрытий, полученных из механически обработанной борсодержащей смеси порошков методом холодного газодинамического напыления

For composite coatings obtained by cold spraying from powder mixtures of composition Al + 50 wt. % B and Al + 50 wt. % B4C, prepared in a V-shaped mixer and mechanical processing in a planetary mill, a comparison of these methods for preparing mixtures for the content of boron (boron carbide) in the coating was carried out. It is shown that, regardless of the method of preparation, the content of boron and/or boron carbide in the coating has close values, which is confirmed by the results of X-ray phase analysis and visual processing of images of the coating structure.

Effect of the content of silane-functionalized boron carbide on the mechanical and wear performance of B4C reinforced epoxy composites

This article presents the mechanical, physical, and tribological properties of the boron carbide (B4C) reinforced epoxy matrix composites (BEMCs). The BEMC samples were prepared with various B4C concentration of 0%, 1%, 2%, 3%, and 5%. B4C particles were treated with a silane coupling agent to ensure efficient adhesion with epoxy. The influence of a range of parameters (particle loading, sliding speed, sliding distance, and normal load) on the wear and friction behavior of BEMCs were evaluated by conducting wear tests under dry sliding conditions on a pin-on-disc wear test set-up. The addition of B4C to the epoxy polymer improved the wear resistance of the composites. Maximum wear resistance and coefficient of friction were observed for the composite with the highest percentage of B4C (5%). The specific wear rate was reduced on increasing load and sliding distance and increased with the sliding velocity. Mechanical properties including compression strength, flexural strength, and impact energy, along with physical properties such as density and hardness, were also evaluated. B4C particles improved the hardness, density, flexural and compression strength, and impact resistance of the composites. Scanning electron microscope (SEM) analysis of the worn-out surfaces and flexural fractured surfaces was carried out to predict the possible wear and fracture mechanisms. Micro-ploughing, abrasion, and adhesion were the wear mechanisms in BEMCs. Under the flexural loads, particulate de-bonding, pull-out, and brittle fracture of the matrix were the governing failure mechanisms.

Study on effect of ceramics on dry sliding wear behaviour of Al-Cu-Mg based metal matrix composite at different temperature

The current global industrial scenario entails a heterogeneity of contemporary material, and its associated process increases product performance such as the capacity to withstand at elevated temperature, higher operating speed, and load. Due to which there has been increasing demand for the newly developed materials. Current study was carried out to explore the effects of ceramics on Al2219 versus un-reinforced Al2219 alloy. According to the current exploration, it clearly says that boron carbide (B4C) and graphite (Gr) content can be an appropriate alternative to Al2219. Stir casting technique was used to fabricate Al2219 and reinforced with Aluminium oxide (Al2O3), B4C & Gr. Scanning electon microscop (SEM) reveals the developed microstructure of Al2219, HMMC (hybrid metal matrix composite), and worn surface morphology. Chosen alloy predominantly consist of Al and Cu-Mg phase. Al having an incoherent interface with a matrix. In high-temperature wear results, the contemporary HMMCs shows significant increases (30%) in wear resistance at (150 °C). Due to the existence of the B4C & Gr reinforcement particulate improves the strengthening kinetics in the matrix phase at 150 °C when compared to Al2219. IBM SPSS Statistics.22 was used to predict the wear properties of the composite. Artificial neural network (ANN) predictive outcomes fit to actual measured data & absolute relative error is < 1%.

Experimental Testing and Fabrication of Metal Matrix Composite for Automotive Applications

Cold compaction behaviour, hardness, and micro-structural behavior of aluminium–boron carbide composites with variable boron carbide content for several composite systems, including Al-5 percent B₄C, Al-10 percent B₄C, Al-15 percent B₄C, and Al-20 percent B₄C, were all evaluated. Powder metallurgy was used to create the particle reinforced composite, with aluminum particles measuring 75 microns and boron carbide particles measuring 150 microns. The compacts were made using a universal testing machine (UTM) with a 60-ton capacity and the appropriate punch and die set assembly. After the green compacts were prepared, they were sintered in an electric furnace at 550°C for 120 minutes. The compacts are then allowed to cool in the furnace to room temperature. Cold compaction and axial pressing were used to study densification tendencies. The link between applied pressure and density, as well as between applied pressure and relative density, was established. The percentage of B₄C reinforcement was used to boost the hardness and compressive strength of various composite samples. Scanning electron microscopy (SEM) images were used to investigate microstructural phenomena. The final solution was compared to that of Cam, an existing car component. It's made of a metal matrix composite of Al-SiC. Because the Al-B₄C composite has a lower density than the Al-SiC composite, it allows for the most weight reduction in the product. The samples' weights have been reduced, resulting in a higher strength-to-weight ratio. In both cases, the material cost evaluations were substantially identical. It's simple to automate the fabrication process.

Neutron Shielding Performance of 3D-Printed Boron Carbide PEEK Composites.

Polyethylene is used as a traditional shielding material in the nuclear industry, but still suffers from low softening point, poor mechanical properties, and difficult machining. In this study, novel boron carbide polyether-ether-ketone (PEEK) composites with different mass ratios were prepared and tested as fast neutron absorbers. Next, shielding test pieces with low porosity were rapidly manufactured through the fused deposition modeling (FDM)-3D printing optimization process. The respective heat resistances, mechanical properties, and neutron shielding characteristics of as-obtained PEEK and boron carbide PEEK composites with different thicknesses were then evaluated. At load of 0.45 MPa, the heat deformation temperature of boron carbide PEEK increased with the boron carbide content. The heat deformation temperature of 30% wt. boron carbide PEEK was recorded as 308.4 °C. After heat treatment, both tensile strength and flexural strength of PEEK and PEEK composites rose by 40%–50% and 65%–78%, respectively. Moreover, the as-prepared composites showed excellent fast neutron shielding performances. For shielding test pieces with thicknesses between 40 mm and 100 mm, the neutron shielding rates exhibited exponential variation as a function of boron carbide content. The addition of 5%–15% boron carbide significantly changed the curvature of the shielding rate curve, suggesting an optimal amount of boron carbide. Meanwhile, the integrated shielding/structure may effectively shield neutron radiation, thereby ensuring optimal shielding performances. In sum, further optimization of the proposed process could achieve lightweight materials with less consumables and small volume.

Investigation on Mechanical Properties and Microstructure of B4C/Graphene Binary Particles Reinforced Aluminum Hybrid Composites

In the present study, boron carbide and graphene-reinforced aluminum hybrid composites with various boron carbide (1, 3, 6, 9, 12, 15, 30 wt%) and graphene nanoplatelets (GNPs) content (0.15, 0.30, 0.45 wt%) were produced by the powder metallurgy method. The method consists of mixing, ultrasonic dispersing, mixing, filtering, drying, pressing, and sintering processes. The apparent density, compressive strength, and Vickers hardness of the fabricated composites were determined by density meter, universal test machine, and micro Vickers hardness measurement device, respectively. The phase and microstructural analysis of the fabricated composites were analyzed using an X-ray diffraction device and scanning electron microscope, respectively. The maximum apparent density (2.54 ± 0.005 g/cm3), the highest Vickers hardness (109.8 ± 1.5 HV), the best compressive strength (244 ± 5 MPa), and minimum porosity (4.0%) were obtained at Al-30%B4C-0.15%GNPs composite. The enhancement in Vickers hardness and compressive strength of Al-30%B4C-0.15%GNPs composite was detected as + 293% and + 190% compared with pure aluminum. In conclusion, it was detected that the mechanical strength of Al-30B4C-GNPs composites improved up to 0.15 wt%GNPs content. After 0.15 wt%graphene content, the mechanical strength of Al-30B4C-GNPs composites decreased due to the agglomerated graphene nanoparticles.

Characterization, corrosion and failure strength analysis of Al7075 influenced with B4C and Nano-Al2O3 composite using online acoustic emission

This paper aims to establish the mechanical, corrosion and failure analysis using online acoustic emission of Al7075 alloy, Al7075-B4C composite and Al7075- B4C-Al2O3 hybrid composite with different Boron Carbide (B4C) content of 5, 10, 15 & 20% and Nano Aluminium Oxide (Al2O3) content of 2% on a weight basis with the high energy stir casting method. The casted samples have been characterized by x-ray Diffraction (XRD), Thermo gravimetric analysis (TGA/DSC), Energy Dispersive Spectrum (EDS), and Scanning Electron Microscope (SEM). In case of hybrid composite, the hardness and the tensile strength decrease when the content of Al2O3 increases. However, in the present research, the addition of B4C with nano Al2O3 particles in certain proportions has increased the hardness and tensile strength. In addition, the tensile fractographs of the specimens were analysed using SEM. Acoustic Emission (AE) method was used for monitoring the acoustic energy that are released at the time of deformation process and early crack detection. The influence of the volume fraction of the B4C particulates on the microstructural and corrosion characteristics of Al7075- B4C with nano Al2O3 metal matrix composites (MMCs) was also studied. It has been observed from the literature that the direct strengthening of composites occurs due to the presence of hard ceramic phase, while the indirect strengthening arises from the thermal mismatch between the matrix alloy and reinforcing phase during solidification. Based on the database for material properties, the application area of HAMCs has been proposed in the present review. The effects of nanomaterial dispersion in the metal matrix and the formation of interfacial precipitates on these properties are also addressed. Particular attention is paid to the fundamentals and the structure–property relationships of such novel Nano composites.

Mechanical behaviour of aluminium based metal matrix composite reinforced with SI3N4 and B4C

This investigation on mechanical and tribological behavior aluminum 6063 boron carbide silicon nitride composite are identified. Aluminum 6063 particles reinforced composites were produced through stir casting route. In the samples of Al 6063 composites were tested for tensile, impact, optical microscope, Scanning Electron Microscope (SEM), EDAX. The test result showed increasing tensile strength, of composites compared with base alloy because of the presence of increased ceramic phase. The wear resistance of the composites increased with increasing content of boron carbide particles The micro structural results showed a grain refinement with the increased in silicon nitride content. The results exhibited with the increase in silicon nitride reinforcement the microhardness improved. The microhardness showed a decreasing trend with increase in identification load and decreasing trend with increasing dwell time. Different % age of reinforcement (13%) is used in the paper. SEM used to investigate the microstructure of the composite. The coefficient of friction decreased with increased boron carbide content and reached its minimum at 5% Boron carbide. The silicon nitride content and reached its minimum at 8%.

Synthesis, microstructure and hardness of Al 7075/B4C/Fly-ash composite using stir casting method

Stir-casting is the appropriate and economical technique for HAMCs synthesis as it produces uniformly reinforcement distributed composite retaining finer grains. In the present work, Al 7075/x%wt.B4C/2%wt. fly-ash HAMCs were fabricated via stir casting route, where x is weight percentage of boron carbide (x = 2, 4, 6 and 8 wt%). Incorporation and distribution of reinforcement particles in HAMCs were analysed using scanning electron microscope (SEM) and optical micrographs. Also, Micro-hardness tests were conducted at seven locals points in hardness specimen to see the variation of hardness values. The coefficient of variation was calculated to ensure uniform hardness values, which further confirm the uniform distribution of reinforcements in the prepared composite. Moreover, mathematical modelling was done to obtain the empirical relation of micro-hardness of composite with respect to fly-ash and boron carbide content, which shows the correlation between the micro-hardness and reinforcements contents in the HAMC. The synthesized HAMCs may be suitable in automobile and aerospace application where low cost, lightweight, high temperature resistant and high wear resistant composite are required.

Effect of Current Variation on Microstructure and Properties of B4C Nickel-base Alloy by Plasma Surfacing

In order to study the hardness of nickel-based alloys and the effect of different mass fraction boron Carbide on the microstructure of nickel-based alloys. In this paper, different amounts of boron carbide are added to the nickel alloy powder. A layer of nickel alloy surface layer is welded on the surface of the Q235 steel plate by plasma surfacing technology. The microstructure of the laminate is observed and analyzed by using Caisijinxiang tissue microscope. The hardness of the welding layer was tested by microhardness meter and the influence of boron Carbide on nickel alloy was obtained. The results show that boron carbide and nickel base alloy are well fused. The surfacing layer is mainly composed of fine dendrites and herbaceous eutectic structures. The addition of boron carbide can significantly improve the hardness andfine structure of the surfacing layer. With the increase of the content of boron carbide, the hardness of the surfacing layer first increases and then decreases. The experimental data show that when the mass fraction contentof boron carbide is 6% and the current is 110A, the hardness of the welding parts is higher.

A comparative study of the mechanical and tribological behaviours of different aluminium matrix–ceramic composites

Aluminium matrix composites (AMCs) have great potential for critical applications within aerospace, automotive, defence, marine, agriculture and nuclear engineering sectors. The composite materials are very attractive because of their good balance between lightweight versus high strength and machinability. Depending on the particular application, these properties can be further enhanced by adding silicon carbide, boron carbide and graphite, respectively. These reinforcements help to upscale the physical/mechanical properties in order to meet the novel industrial demand. In the present work, a novel hybrid composite is developed through stir cast welding technique. The novel materials manufactured are of great importance, because they exhibit higher mechanical properties and better wear resistance with respect to classical materials (i.e. pure aluminium). The results of mechanical test showed that the addition of 5% boron carbide content to aluminium matrix permits to enhance the tensile properties, shear strength and hardness values; 6% silicon carbide and 4% graphite allow to improve the flexural strength and wear rate, respectively. The best performance was obtained for aluminium composite with 5 wt% boron carbide. The correlation between industrial requirements and the findings from this research indicates that the newly developed composite is an excellent candidate material for structural neutron absorber, armour plate and as a substrate material for computer hard discs.