Nanoceramic Particles Research Articles

Optimization of low temperature hydrogen sensor using nano ceramic-particles for use in hybrid electric vehicles

Optimization of low temperature hydrogen sensor using nano ceramic-particles for use in hybrid electric vehicles

Formation of Self-Assembled Monolayer and Characterization of AA7075-T6/B4C Nano-ceramic surface composite using Friction Stir Processing

In the present study, fabrication of surface composite using AA7075-T6 as a matrix material and boron carbide nanoparticles as reinforcement through Friction stir processing (FSP) has been done. FSP technique has been widely utilized for surface modification and the formation of composite material. The B4C nanoparticles size (<30 nm) as reinforcement were padded in dimension of 2 mm width and 1.5 mm depth groove of AA7075-T6 plate as a matrix material. The single-pass process executed using a square tool pin with tool rotation and traverse speed of 1000 rpm and 40 mm min−1 respectively. This research aims to observe and process Self-Assembled Monolayer (SAM), investigate the effect of the B4C nano-ceramic particles on the AA7075-T6 and its mechanical properties of the nano-ceramic surface composite. Frictional and wear analysis investigations under various physical conditions have highlighted surface durability characteristics of the metal matrix composite of AA7075-T6. Microstructure results along with fractography-image highlight the homogeneous distribution of boron carbide nano-ceramic particle. Tensile test, Microhardness, microstructure, Field Emission Scanning-Electron Microscope (FESEM), and X-Ray Diffraction (XRD) analyzed the fabricated (Al + B4C) nano-ceramic surface composite. The fabricated nano-ceramic surface composite could be utilized in lightweight applications such as aerospace, marine, defence, and automotive industry.

Grain refinement and localized amorphization of additively manufactured high-entropy alloy matrix composites reinforced by nano ceramic particles via selective-laser-melting/remelting

Abstract Nano TiN-particle reinforced CoCrFeMnNi high-entropy alloy (HEA) matrix composites were additively manufactured via selective laser melting (SLM) and that with a remelting laser-scan strategy (RLSS). The RLSS process promoted the reinforcement-dispersity and thus further refined the HEA matrix grains. The generated hybrid amorphous-crystalline microstructure was benefited by RLSS-SLM to enhance strength and regulate plasticity. The dispersion behaviors and effects of nano TiN-particles were expounded. The amorphous formation mechanism was also discussed.

Ultrasonication Assisted Fabrication of Aluminum and Magnesium Matrix Nanocomposites - A Review

Recent researches in the domain of casting confirmed that the mechanical properties of aluminum and magnesium based nanocomposites can be appreciably enhanced when ultrasonic cavitation assisted solidification processing is used. Ultrasonic cavitation assisted solidification processing is used for the manufacturing of aluminum and magnesium alloy based metal matrix nanocomposites reinforced with nanoceramic particles. In this solidification processing, formation of clusters have been minimized and the nanoreinforcements were distributed uniformly in aluminum and magnesium matrix nanocomposites. The ultrasonic assisted casting approach will manage the grain dimensions via minimizing agglomeration of nanoparticles in metal matrices. This paper opinions the properties and morphology of aluminum and magnesium based metal matrix nanocomposites fabricated through ultrasonic assisted casting process.

Fabrication of nano-TiC functional gradient wear-resistant composite coating on 40Cr gear steel using laser cladding under starved lubrication conditions

Under starved lubrication conditions, gears are subjected to excessive wear and are therefore prone to failure. The laser cladding of nano titanium carbide (TiC) composite functional gradient coatings on a gear’s surface is an effective way to improve the wear resistance and service life of the latter. In this paper, a laser-cladded gradient coating was prepared on a 40Cr gear steel surface using a pre-prepared nano-TiC powder and a 12CrNi2 powder. During the preparation of the coating, the nano-TiC powder was gradually increased along the gradient direction. The phase composition and microstructure of the coating material were then characterized by scanning X-ray diffraction (XRD) and scanning electron microscopy (SEM). The respective surface roughness, micro-hardness and wear resistance of the gradient coatings were also tested. The results showed that the TiC was transformed from nanoceramic particles embedded in the coating interior to an agglomerated large-volume hard phase structure as the pre-prepared nano-TiC powder increased. The micro-hardness gradually increased from 612 HV at the bottom of the gradient coating to 1088 HV at the top. With the increase in micro-hardness and the transformation of TiC into a hard phase, the gradient coating showed a 50% reduction in friction coefficient, a 40% reduction in grinding loss, and a significant increase in wear resistance under heavy load and starved lubricant conditions. The research further showed that the nano-TiC gradient functional coating is an ideal choice for improving the service life of gear.

Magnesium/Nano-hydroxyapatite Composite for Bone Reconstruction: The Effect of Processing Method

Nano-ceramic particles can serve as reinforcing agents for metallic materials to improve their mechanical properties. However, it is important to ensure chemical compatibility between the matrix and particles. In the present study, magnesium composites with and without nano-hydroxyapatite (nHA) particles were fabricated for bone reconstruction applications. Two different techniques were used, Conventional Sintering (CS) of powder compacts and Spark Plasma Sintering (SPS) of pre-compacted powder. Results showed that a 10 wt% addition of nHA particles to magnesium, followed by SPS improved the compression strength by 27%. CS did not lead to any significant improvement compared to SPS processing. X-ray diffraction data after CS revealed the formation of unfavorable phases due to chemical reactions between nHA particles and the magnesium matrix, while these phases were absent after SPS processing. The mechanical properties of the specimens fabricated by CS were much inferior to those processed using SPS. The shorter processing time associated with SPS leaded to reduced interaction between nHA particles and the Mg-matrix, compared to CS.

Low-velocity impact behavior of glass fiber epoxy composites modified with nanoceramic particles

The introduction of new type of nanomaterials has provided challenges in a deeper level understanding of mechanical behavior and failure mechanisms of fiber-reinforced composites. In this study, a comparison of low-velocity impact behavior of E-Glass epoxy composites modified with 10 wt% nanosilica and 2.5 wt% Nafen™ alumina nanofibers manufactured using vacuum-assisted resin transfer molding is reported. Low-velocity impact tests at three impact energies of 29 J, 39 J, and 50 J are conducted and impact responses, such as impact strength, absorbed energy, and damage area are determined and compared for the two nanoparticles. The damage sustained by composite samples is evaluated by optical microscopy and infrared thermography. Nanosilica-incorporated composites showed rigid behavior, whereas alumina nanofiber-modified composites showed increased stiffness at increased energy of impact as observed from the initial stiffness and deflection of samples. The degree of damage in case of 10 wt% nanosilica-modified composites is reduced by 7.04%, 3.96%, and 7.92% for energy levels of 29 J, 39 J, and 50 J respectively when compared to nonmodified composites, whereas 2.5 wt% alumina nanofiber-modified composites showed 1.66%, −7.35%, and 26.39% for energy levels of 29 J, 39 J, and 50 J, respectively.

Characterization of nano ceramic composite of Mullite-Magnesia-Yttria stabilized Zirconia system

The oxide and nano ceramic system of Mullite-Magnesia-Yttria Stabilized Zirconia were studied. Some fracture toughness models were examined to evaluate the crack length parameter to comply with Palmqvist and median crack criteria at c/a ratio equal to 3.0. The mullite crystal structure was observed using SEM and looks likely needle, whereas 3YSZ crystal appears smoother. Through EDS analysis, it detected the oxides in Mullite system, i.e., Al2O3, and SiO2. With a similar method, some oxides observed in the Mullite-Magnesia-3YSZ system such as MgO, Al2O3, SiO2, Y2O3, and ZrO2. With XRD analysis, nano MMZ system shows containing Al6Si2O13, Corundum (Al2O3), Zirconia (ZrO2), and Quartz (SiO2). Fracture toughness KIC of the ceramic composite of nano mullite-magnesia-zirconia complies with Palmqvist and median crack criteria. Nano ceramic particle shows a higher value of hardness and fracture toughness while compared with oxide ceramic system.

Ultrafast thermomechanical effects in aerosol deposition of hydroxyapatite nanoparticles on a titanium substrate

Hydroxyapatite [Ca10 (PO4)6 (OH)2] is the main mineral component of bone and teeth and is widely used for implant coatings due to its desirable osteoconductive and bioactive properties which are necessary for early bone formation. Aerosol deposition (AD), a novel coating method using a cold vacuum spray, offers the opportunity to produce robust, dense and pore-free coating by nanoceramic particles such as hydroxyapatite (HA). However, the high-velocity impact of HA particles with underlying substrates such as titanium is poorly understood. Here we use large-scale molecular dynamics simulations that reveal the mechanical deformation, stress and temperature during the fast impact of a 3 nm HA particle on a titanium surface. The effect of deposition velocity on deformation and the development of mechanical stresses and temperature of particle and substrate are discussed. We show that during an ultrahigh strain rate (>1010 s−1) deformation process, the temperatures of particle and substrate rise within a few picoseconds to ~1100–1253 K depending on the velocity. However, the particle and substrate temperatures remain lower than their melting temperatures. The simulations capture the initial elastic deformation and subsequent yield and plastic deformation of the particle. The dependence of particle penetration depth and structural transformation of the top layers of titanium on particle velocity is studied, revealing ultrafast mechanisms of particle–substrate bonding.

Effects of Nano-Ceramic Particle Addition for Cold Sprayed Fluoropolymer Coatings

Semi-crystalline polymers such as fluoropolymers are extremely difficult to coat with using solid-state deposition technique such as cold spray (CS) due to its high viscoelastic-viscoplastic behavior. Generally, fluoropolymers solid-state deposition using CS are characterized by a relatively low deposition efficiency (DE) as compared to metallic materials using this deposition technique. In this article, the study on the effect of hydrophobic fumed nanosilica (FNS) and fumed nanoalumina (FNA) in Perfluoroalkoxy (PFA) solid-state deposition using CS has been studied. This study incorporated certain parameters related to the CS process. In addition, powder modification technique using hydrophobic FNS and FNA as additive to feedstock has been studied as well. The results show a number of parameters affected the DE; particle size, traverse speed, gas temperature, and addition of hydrophobic fumed nanoparticles, indicated a better DE. Moreover, PFA coating produced in this manner, retained its hydrophobicity.

Influence of nanoceramic interlayer on polymer consolidation during cold-spray coating formation

Nanoceramic interlayers at the polymer-polymer interfaces have been demonstrated to be extremely vital for the coating buildup (up to 4 mm thickness) during cold-spray consolidation of Ultra-High Molecular Weight Polyethylene (UHMWPE). This paper investigates the polymer-polymer interface formation and strength as a function of the compressive state of the consolidation and the influence of the interlayers at the bonding interface. The research study suggested that the polymer-polymer interfaces get reinforced at high compressive consolidation by two in-situ mechanisms: (i) formation of core-shell surface composites; (ii) formation of a network of polymer-nanoceramic-polymer knots during the polymer chain inter-diffusion. On the other hand, a low compressive consolidation fails to create the surface compositing and polymer-nanoceramic-polymer links at the polymer-polymer interface yielding a weaker interface strength compared to that of a polymer-polymer interface. The nanoceramic particles in the interlayer, in this case, acted as a defect preventing efficient wetting and subsequent inter-diffusion between adjacent polymer particles.

Effect of different heat treatments and varying volume fraction of nano-Al2O3 particles on the hardness and wear resistance of Al 7150 alloy matrix composite synthesized by hot uniaxial compaction technique

The effect of three types of heat treatment and the addition of varying volume fraction of nano-Al2O3 particles on the hardness and wear resistance of Al 7150 alloy matrix composite produced by hot uniaxial compaction technique was investigated. Initially the Al 7150 alloy was synthesized from elemental powders (Al–88.265%, Cr–0.04%, Cu–2.3%, Fe–0.15%, Mg–2.35%, Mn–0.1%, Si–0.12%, Ti–0.06%, Zn–6.5%, Zr–0.115%) using planetary ball milling process. The Al 7150 alloy powders were later blended with varying volume fraction (0, 5, 10 and 15%) of nano-Al2O3 (40–50 nm) particles. The blended Al 7150 alloy composite powders were hot pressed at 400 °C. The compaction pressure was 500 MPa with a compaction time of 1 h before ejection. The hot compacted samples were later subjected to three types of heat treatment processes viz. T6, HTPP and RRA (retrogression and reaging). The microhardness (VHN) of the hot compacted samples increased with the increase in the addition of nano-ceramic particles. The VHN test results of the aged (T6, HTPP andRRA) samples showed higher hardness and the improvement in hardness was 44.11% for T6 sample when compared to the non-aged sample. XRD analysis revealed the occurrence of the stable MgZn2 precipitate phase, which played a significant role in the enhancement of its hardness and wear resistance. The wear behavior of the non-aged and aged samples was analyzed using a pin on disc wear testing machine. The wear test results demonstrated a tremendous enhancement of wear resistance of the T6 aged samples followed by RRA and HTPP treated samples compared to the non-aged samples. Wear surface morphology was studied using FESEM analysis to determine the wear mechanism.

Surface modification of AZ61 magnesium alloy with nano-Al&lt;SUB align="right"&gt;2O&lt;SUB align="right"&gt;3 using laser cladding technique: optimisation of wear properties through hybrid GRA-PCA

The aim of this research is to investigate the wear behaviour of surface modified AZ61 magnesium alloy with nanoceramic reinforcement (Al2O3), done by laser cladding technique. Nano-Al2O3 is added in three different weight proportions, viz., 5%, 10% and 15% on to the surface of AZ61 using Nd:YAG laser. Dry sliding wear behaviour of the surface modified AZ61 material is studied considering various reinforcement of nanoceramic particles, and by varying the speed and axial load in the pin-on-disc apparatus. Experiments were designed using Taguchi's design of experiments and the measured outputs, viz., wear, coefficient of friction and frictional force were analysed using grey relational analysis (GRA), coupled with principal component analysis (PCA) for multivariate optimisation by calculating multi-response performance index (MRPI). Using SEM image, distribution of particles in the magnesium alloy matrix is studied. It is observed that the % reinforcement of nanoceramic particles on the surface of AZ61 alloy is the most critical factor that contributes by 79.30% towards the MRPI, followed by 9.91% contribution by load and speed by 7.94%, as determined from analysis of variance (ANOVA). From confirmation experiment, the optimised condition shows an improved wear resistance obtained from the surface modified magnesium alloy.

Modeling and simulation for mechanical behavior of modified biocomposite for scaffold application

Bones in the human body are a natural composite material that can be fractured due to impact stress and excessive loads. Human bones become less dense and strong when age increases, thereby they become more susceptible to fracture. The present work aims to study the effect of adding nano-ceramic particles on the mechanical properties to fabricate four types of hybrids of Titanium dioxide (TiO2) and Alumina (Al2O3) reinforced polyetheretherketone (PEEK) biocomposites. The objective of this study is to develop and improve the biomechanical properties of the fabricated biomaterials to withstand the loads of the daily human activities. Modeling and analysis of femur bone biomechanics were implemented by using the SOLIDWORKS 17.0 and the finite element ANSYS 15.0 software programs. The response surface methodology (RSM) technique and the Design Expert 11.0 software program were used to improve and verify the results of biomechanical performance of the fabricated biocomposites. From the current research results, it was deduce that the maximum equivalent (von- Misses) and shear stresses on the modeled femur bone are 120,93 and 60,80 MPa. The tensile for modeling the fabricated 20 vol. % TiO2/5 vol. % Al2O3/PEEK biocomposite material is higher than the one of natural femur bone by 10%. The maximum strain energy and the maximum equivalent elastic strain were reduced by 20% and 26,09 %, respectively. The stress safety factor values increased in 5,81%, and the fatigue life for the fabricated biocomposite is more than 40,43%, when compared with natural femur bone material.

Surface modification of AZ61 magnesium alloy with nano-Al&lt;SUB align="right"&gt;2O&lt;SUB align="right"&gt;3 using laser cladding technique: optimisation of wear properties through hybrid GRA-PCA

The aim of this research is to investigate the wear behaviour of surface modified AZ61 magnesium alloy with nanoceramic reinforcement (Al2O3), done by laser cladding technique. Nano-Al2O3 is added in three different weight proportions, viz., 5%, 10% and 15% on to the surface of AZ61 using Nd:YAG laser. Dry sliding wear behaviour of the surface modified AZ61 material is studied considering various reinforcement of nanoceramic particles, and by varying the speed and axial load in the pin-on-disc apparatus. Experiments were designed using Taguchi's design of experiments and the measured outputs, viz., wear, coefficient of friction and frictional force were analysed using grey relational analysis (GRA), coupled with principal component analysis (PCA) for multivariate optimisation by calculating multi-response performance index (MRPI). Using SEM image, distribution of particles in the magnesium alloy matrix is studied. It is observed that the % reinforcement of nanoceramic particles on the surface of AZ61 alloy is the most critical factor that contributes by 79.30% towards the MRPI, followed by 9.91% contribution by load and speed by 7.94%, as determined from analysis of variance (ANOVA). From confirmation experiment, the optimised condition shows an improved wear resistance obtained from the surface modified magnesium alloy.

Effect of boron carbide nano particles in CuSi4Zn14 silicone bronze nanocomposites on matrix powder surface morphology and structural evolution via mechanical alloying

In the present research work, [82Cu4Si14Zn]100-x – x wt% B4C (x = 0, 3, 6, 9, and 12) nanocomposite powders had synthesized by mechanical alloying (MA). The MA process had carried out in a single vial high-energy planetary ball mill with the ball-to-powder ratio of 10:1 for 20 h. The results had revealed that the addition of B4C nano-ceramic particles had contributed more reduction on Cu-Zn-Si matrix powder particle size, changes in shapes, and structural refinement. The synthesized nanocomposite powders had characterized by advanced microscopes. The calculated average nanocomposite powder particle size was 13 ± 1.2 µm, 9 ± 0.8 µm, 5 ± 0.65 µm, 3 ± 0.4 µm, and 1 ± 0.25 µm for 0, 3, 6, 9, and 12 wt% B4C reinforced nanocomposite powders respectively. Further, an average nanocrystallite size of 84 nm had obtained for [CuSi4Zn14]-0% B4C sample whereas 13 nm had achieved for [CuSi4Zn14]-12% B4C sample. This had attributed by variation in repeated cold welding, severe plastic deformation, and fragmentation of mechanical collisions with the function of boron carbide (B4C) nano-ceramic particles in Cu-Zn-Si matrix. In addition, the laser powder particle size (diameter, μm) and its distribution at D100, D10, D5, D1, D0.1, and D0.01 with the function of the percentage of B4C ceramic particles had also studied and investigated.

Nano-SiCP particles distribution and mechanical properties of Al-matrix composites prepared by stir casting and ultrasonic treatment

Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-metal process combined with high energy ball milling and ultrasonic vibration methods. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850 ℃ to form an oxide layer with a thickness of approximately 3 nm. The mm-sized composite granules containing nano-SiCp were firstly produced by milling the mixture of oxidized nano-SiCp and pure Al powders, and then were remelted in the matrix-metal melt with mechanical stirring and treated by ultrasonic vibration to prepare the composite. SEM analysis results show that the nano-SiC particles are distributed uniformly in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the composite with 2wt.% nano-SiCp in as-cast state are 226 MPa and 5.5％, improved by 20％ and 44％, respectively, compared with the A356 alloy.

DC-EPD of nanoceramic particles accelerated via anodic dissolution in organic media

AbstractThis paper presents the fabrication of nanoceramic layers by electrophoretic deposition. Suspensions containing TiO2 nanoparticles were prepared in different organic solvents, such as ethanol, methanol, acetone, and acetylacetone. During electrophoretic deposition, the color of organic media at around 200 V cm−1 began to change. This phenomenon is related to the anodic dissolution, which may assist deposition processes in some cases. Deviation from Hamaker's equation was observed upon measuring the deposited mass using different anode electrodes. Atomic absorption spectroscopy was used to measure concentrations of chemical elements liberated in the suspension due to the dissolution of anodes. These results show that anodic dissolution directly affects deposition rate. We observed this event even in the absence of powder and additives. Therefore, this is advantageous if anodic contaminants are not effective or influential.

Processing and characterization of Al-Al3Nb prepared by mechanical alloying and equal channel angular pressing

Mechanically alloyed Al with immiscible elements such as Nb can lead to a uniform distribution of nanoscaled precipitates which are highly stable compared to conventional alloying and with excellent interface, resulting in significant increase in strength without problems associated with nano ceramic particles in metal matrix composites. Although immiscible, Nb can be alloyed with Al through mechanical milling, forming trialuminide (Al3Nb), either directly or upon subsequent precipitation, which possesses high strength, stiffness and stability at elevated temperatures. In the present study, Al-5 at.% Nb supersaturated solid solution was achieved after prolonged ball milling and nano Al3Nb precipitates were formed during subsequent ageing at 530°C. The Al-Al3Nb powder was consolidated by equal channel angular pressing (ECAP) at 400°C, resulting in a fully dense material with a uniform distribution of nanoscaled Al3Nb precipitates in the Al matrix.

Manufacturing of Al–Al2O3–Mg multilayered nanocomposites by accumulative roll bonding process and study of its microstructure, tensile, and bending properties

Accumulative roll bonding is used for producing multilayered composites, with exciting mechanical properties, via the creation of bonding between dissimilar metallic layers. In this study for the first time, Al–Mg multilayered composites reinforced with nano-Al2O3 particles were produced by the accumulative roll bonding process at different temperatures. However, there was a problem regarding the adhesion of the nanoceramic particles with each other and with the sheet metals. To avoid these disadvantageous effects of the Al2O3 particle addition and to create better adhesion at interfaces, Al and different percentages of Al2O3 powders were ball milled and Al/Al2O3 composite powders were produced. Afterward, the composite powder was added between Al and Mg sheets and they were rolled to 50% reduction in thickness in each cycle. The process was continued up to four cycles at different temperatures. The microstructural evaluation and mechanical properties of aluminum/nanoalumina/magnesium composites showed that 300℃ is suitable temperature for accumulative roll bonding of Al and Mg sheets with nano-Al2O3 particles. Accumulative roll bonded composites with Al/5 wt% Al2O3 composite powder showed higher tensile strength while the maximum bending strength was related to the composites containing Al/10 wt% Al2O3. Fracture surfaces of the nanocomposites revealed a brittle fracture at higher cycles.