Increase In B4C Content Research Articles

A study on the improvement of wear and corrosion properties of ZA40/Graphene/B4C hybrid nanocomposites

The objective of the study was to investigate the production and evaluation of ZA40/Graphene/B4C hybrid nanocomposite (HNC). To fabricate the HNC powders (HNPs) involved the combination of graphene nanoplatelets and B4C micro-particles with ZA40 powders through mechanical milling. The graphene content remained constant 1 wt%, while the B4C content varied at 1 wt%, 2 wt%, and 3 wt%. After an 8-hour milling process, the HNPs were subjected to hot-pressing to create bulk HNC samples. Various tests, including microstructural analysis, hardness, tensile strength, wear resistance, and corrosion resistance, were conducted on the consolidated samples. The results indicated that the HNC sample containing 3 wt% B4C (S3) exhibited the most favorable properties. This sample displayed a hardness value of 181 HB, significantly higher than the ZA40 matrix alloy's hardness of 133 HB. Moreover, its ultimate tensile strength measured at 243 MPa, which was much higher than the ZA40 matrix alloy (157 MPa). The wear resistance of HNCs increased significantly with an increase in B4C content. The sample containing 3 wt% B4C demonstrated approximately 3.5 times greater corrosion resistance than the unreinforced ZA40 matrix alloy.

Microstructural evaluation and wear behavior of B4C particle reinforced TiO2-SiO2-ZnO compound by hot-pressing method

In this study, different wt% of B4C material added to TiO2, ZnO, and SiO2 materials known with distinguished properties by hot-pressing method to produce new materials. Characterization of the materials was performed by using XRD, SEM and EDS. The micro-hardness of the materials was measured and the wear characteristics of B4C-added materials were determined by subjecting them to wear loads of 5 N, 10 N and 15 N. In XRD, it was observed that the intensity of the peak was decreased depending on the increase in B4C content. In SEM, it was determined that there was a two-phase structure with complex boundaries and indefinite grain boundary formation. Besides, it was determined that elements in the EDS and the compounds in the XRD supported each other. In wear analyses, it was seen that as the wear load increased, the depth and width of the wear track in all materials increased. Furthermore, as the weight ratio of B4C material in the composition was increased, the weight loss at different wear loads was decreased and the lowest weight loss was found in Ti45Si15Zn20B20 material. Moreover, it was observed that the wear track and its depth were inversely proportional to the increasing B4C content in the compound. Friction coefficients of the materials under 5 N wear load varied between 0.15–0.43, whereas under 10 N and 15 N wear load, it varied between 0.09–0.28 and 0.06–0.29, respectively. While the hardness value of B4C-free Ti60Si20Zn20 was 260 HV, the highest hardness value was seen in Ti45Si15Zn20B20 material as 1010 HV.

Evolution of Physical and Mechanical Properties of Al5083/B4C Composites fabricated through Stir Casting

Abstract In the present work, Aluminium composites were fabricated through conventional stir casting process. The composites were fabricated at 800°C inside the electric furnace in the presence of inert gas. AA5083 and B4C particulates with varying weight % of 5, 10, 15 and 20 were used as the starting materials. The microstructure of the composites was examined using scanning electron microscopy (SEM). The physical and mechanical properties of the composites were investigated and the results show that the increase in B4C content in the aluminium matrix increases the tensile strength and hardness of the composites to a significant level. The decrease in density accompanied by increase in porosity was also observed with the increase in B4C.

Application of Taguchi’s method to study the effect of processing parameters of Al6082/B4C/Al2SiO5 hybrid composites on mechanical properties

In the present study, Al6082 hybrid composites with multiple reinforcements B4C and Al2SiO5 was fabricated using stir casting technique. The effect of processing parameters such as stirring speed and stirring time along with varying B4C content (4% to 12%) on mechanical properties such as hardness, tensile and impact strength was studied. The tests were performed based on Taguchi’s L9 orthogonal array followed by analysis of results by analysis of variance (ANOVA). The microstructure and fracture surface of hybrid composites after impact and tensile were studied using scanning electron microscope (SEM). It was found that the dispersion of multiple reinforcements were uniform throughout the matrix along with good interfacial bonding. The mechanical properties were found to increase with the increase in B4C content of up to 8%. The analysis results showed reinforcement content as the most influential parameter followed by stirring time and stirring speed.

Using B₄C Nanoparticles to Enhance Thermal and Mechanical Response of Aluminum.

In this work, Al-B4C nanocomposites were produced by microwave sintering and followed by hot extrusion processes. The influence of ceramic reinforcement (B4C) nanoparticles on the physical, microstructural, mechanical, and thermal characteristics of the extruded Al-B4C nanocomposites was investigated. It was observed that the density decreased and porosity increased with an increase in B4C content in aluminum matrix. The porosity of the composites increased whereas density decreased with increasing B4C content. Electron microscopy analysis reveals the uniform distribution of B4C nanoparticles in the Al matrix. Mechanical characterization results revealed that hardness, elastic modulus, compression, and tensile strengths increased whereas ductility decreases with increasing B4C content. Al-1.0 vol. % B4C nanocomposite exhibited best hardness (135.56 Hv), Young’s modulus (88.63 GPa), and compression/tensile strength (524.67/194.41 MPa) among the materials investigated. Further, coefficient of thermal expansion (CTE) of composites gradually decreased with an increase in B4C content.

Inhibitor effects of sodium benzoate on corrosion resistance of Al6061-B4C composites in NaCl and H3BO3 solutions

Sodium benzoate (SB) is used for the first time to inhibit the corrosion of Al6061-B4C composites in H3BO3 and NaCl solutions. Al6061100−x–x wt% B4C (x = 0, 5, and 10) composites are manufactured by a powder metallurgy route. The corrosion inhibition efficiency of SB is investigated as a function of the volume fractions of B4C particles by using potentiodynamic polarization and electrochemical impedance techniques. Without the use of an inhibitor, an increase of the B4C particles in the composite decreases the corrosion resistance of Al6061-B4C composites. It is found that SB is an efficient corrosion inhibitor for Al6061-B4C composites in both investigated solutions. The corrosion inhibition efficiency of SB increases with an increase in B4C content. Since SB is an adsorption type inhibitor, it is envisaged that an extremely thin layer of molecules adsorbs onto the surface and suppresses the oxidation and reduction. It is found that the inhibitor effect of SB is more pronounced in a H3BO3 environment than in NaCl solution. Further, the mechanism of corrosion inhibition by SB is illustrated by using optical and scanning electron microscopy of corroded samples. It is found that the adsorption of benzoate ions on the Al surface and its bonding with Al3+ ions forms a hydrophobic layer on top of the exposed Al surface, which enhances the protection against dissolved boride ions.

Mechanical, corrosion and wear characteristics of powder metallurgy processed Ti-6Al-4V/B4C metal matrix composites

Titanium alloys are used in aerospace and automotive applications because of its high specific strength, stiffness and good machinability but its wear resistance is inadequate. To eliminate this property lag Boron Carbide (B4C) ceramic particles are reinforced with Ti-6Al-4V through powder metallurgy route (PM). Reinforcement particles are mixed with base alloy for the weight percentage of 0, 5 and 10 so as to analyse the effect of reinforcements on mechanical, corrosion and wear properties. This research outcome corresponds to decreased density, increased hardness and corrosion resistance capability for significant increase in B4C content of the newer composite developed and tested. Applied load signify higher effect on wear performance of the composite specimens followed by B4C addition percentage. Scanning Electron Microscope results reveal that B4C reinforced Ti-6Al-4V composite comprise for higher wear resistance and illustrate mild worn surface when compared to that of unreinforced Ti alloy.

Preparation of multi-phase composite of tungsten carbide, tungsten boride and carbon by arc plasma melting: characterization of melt-cast product

Arc plasma melting of WC+B4C followed by an in situ furnace cooling produced a multi-phase composite consisting of tungsten carbide, tungsten boride and carbon. The melt-cast product was prepared in six different compositions by varying the boron carbide content (within 1–15wt%) at the charge stage. XRD, SAED and XPS characterizations of the product showed the major phases to constitute of W2B, WB, W2B5 (WB2), WC, W2C and C. Carbon was found to exist in three different forms, such as graphite, diamond / DLC and nanocrystalline diamond (C–C sp3 coordination). FESEM, TEM and BET studies revealed the surface morphology, microstructure and non-porous nature of the composites respectively. From micro Raman spectra it was evident that W2C and all tungsten boride phases were non-Raman active with 514nm radiation (Ar+ laser). Preliminary mechanical characterization of the polished composite samples (in solid forms) showed the hardness to increase with increase in B4C content (range: 1–10wt%). An extraordinary hardness of 3835±80 VHN with corresponding Young’s modulus of 695±33GPa was observed for the typical composition of WC+10wt% B4C. However, the hardness showed decreased value for 15wt% B4C added sample.

Effect of the content of B4C on microstructural evolution and wear behaviors of the laser-clad coatings fabricated on Ti6Al4V

TiNi/Ti2Ni-based composite coatings reinforced by TiC and TiB2 were produced on Ti6Al4V by laser cladding the mixture of a Ni-based alloy and different contents of B4C (0wt%, 5wt%, 15wt%, and 25wt%). The macromorphologies and microstructures of the coatings were examined through optical microscopy, X-ray diffractometry, scanning electron microscopy, and energy dispersive spectrometry. The microhardness, fracture toughness, and wear behaviors of the coatings were also investigated by using a microhardness tester and an ultra-functional wear testing machine. Results showed that the coatings were mainly composed of TiNi/Ti2Ni and TiC/TiB2 as the matrix and reinforcement particles, respectively. The phase constituents of the coatings were not influenced by addition of different contents of B4C. The microstructure of the reinforcements in the coatings presented the following evolution: hypereutectic consisting of blocky (TiC+TiB2)e eutectic and primary TiCp cellular dendrites (0wt% B4C), mixture of hypereutectic and willow-shaped (TiB2+TiC)p pseudoeutectic (5wt% B4C), and pseudoeutectic (15 and 25wt% B4C). With increasing B4C content, the volume fraction and size of the pseudoeutectic structures as well as the average microhardness of the coatings (850, 889, 969, and 1002HV0.2) were increased. By contrast, the average fracture toughness of the coatings was gradually decreased (4.47, 4.21, 4.06, and 3.85Mpam1/2) along with their wear volumes (0wt%, 5wt%, and 15wt% B4C). The increase in B4C content to 25wt% did not further reduce wear loss. The wear mechanism transformed from micro-cutting (0wt% B4C) into a combination of micro-cutting and brittle debonding (5wt% B4C) and finally led to brittle debonding (15wt% and 25wt% B4C). Coatings with suitable contents of B4C (less than 15wt%) showed excellent comprehensive mechanical properties.

Creep behavior and wear resistance of Al 5083 based hybrid composites reinforced with carbon nanotubes (CNTs) and boron carbide (B4C)

In the current research, aluminum based hybrid composite reinforced with boron carbide (B4C) and carbon nanotubes (CNTs) was produced by powder metallurgy method. creep behavior, wear resistance, surface roughness, and hardness of the samples were investigated. To prepare the samples, Al 5083 powder was milled with boron carbide particles and carbon nanotubes using planetary ball mill under argon atmosphere with ball-to-powder weight ratio of 10:1 for 5 h. Afterwards, the milled powders were formed by hot press process at 380°C and then were sintered at 585°C under argon atmosphere for 2 h. There was shown to be an increase in hardness values of composite with an increase in B4C content. The micrograph of worn surfaces indicate a delamination mechanism due to the presence of CNTs and abrasion mechanism in composite containing 10 vol.%B4C. Moreover, it was shown that increasing B4C content increases the wear resistance by 3 times under a load of 20 N and 10 times under a load of 10 N compared to CNTs-reinforced composite. surface roughness of the composite containing 5 vol.%CNT has shown to be more than other samples. The results of creep test showed that adding carbon nanotubes increases creep rate of Al 5083 alloy; however, adding B4C decreases its creep rate.

Analysis of Cooling Curves, Microstructure and Properties of Chill Cast Al-B<sub>4</sub>C Composites

The cooling rate depends on the properties of the mold material which has significant influence on the formation of microstructure and in turn on the properties of the cast components. This work is aimed at preparing the Al-B4C composite using different chill materials by gravity die casting and recording the casting temperature during pouring and subsequent solidification to analyze the cooling rate of the casting. The effect of chilling on the microstructure and mechanical properties are determined. The cast specimens are cut and polished by standard metallographic procedure. Optical micrographs are taken at different magnification to reveal the microstructure and B4C particulate distribution. The micro hardness and tensile test results indicate that there is a significant increase in these properties with the increase in B4C content.

Hardness and tensile strength study on Al356–B4C composites

Additions of high modulus particles to aluminium alloys offer the potential to develop a lightweight composite with high strength and hardness. Al356 matrix composites reinforced with B4C particles were prepared using stir casting method. Hardness and tensile strength of unreinforced alloy and composites with different volume percentages of boron carbide particles were measured and compared. Microstructural characterisation revealed an almost uniform distribution of the B4C particles in the matrix. It also showed that the grain size of aluminium composite is smaller than that of monolithic aluminium. X-ray diffraction studies also confirmed the existence of boron carbide and some other reaction products, such as AlB2 and Al3BC, in composite samples. It is observed that the mechanical properties enhance with increasing particle fraction. The great enhancement in values of ultimate tensile stress and hardness observed in this experiment is due to small particle size and good distribution of the B4C particles, which was confirmed by SEM images. According to the results of this experiment, quite significant improvement in strength is noted when 10 vol.-%B4C particles is added; a further increase in B4C content leads to a reduction in strength values. This might be the result of greater agglomeration of particles and higher degree of microporosity present in the composite at higher B4C content.

Mechanical properties and wear behavior of Al–2wt.% Cu alloy composites reinforced by B4C nanoparticles and fabricated by mechanical milling and hot extrusion

Tensile and wear properties of a nanostructured matrix of Al prepared via mechanical milling and hot extrusion were investigated before and after incorporation of B4C nanoparticles. Nanocomposite samples were prepared using mechanical milling technique associated with incorporating 2 and 4 wt.% of B4C nanoparticles into the matrix of Al. Results showed that increase in B4C content yields a narrow size distribution of fine particles and also smaller size of crystallite after the mechanical alloying process. Tensile, microhardness and wear tests (pin-on-disk) were used to characterize the hot extruded samples. The results revealed a lower wear rate, higher yield strength, tensile strength and hardness for nanostructured Al matrix in contrast to the commercial coarse grained Al matrix. The same trend was also found to be valid for the nanocomposite samples with respect to the base matrix.