Reinforcement Particle Size Research Articles

The impact of the diamond reinforcing particle size on their interaction with the aluminum matrix of composites in the course of heating

In aluminum matrix composites, the formation of aluminum carbide may occur during heating on contact between aluminum and the carbon reinforcing particles. Samples of composites with an aluminum matrix and various diamond reinforcing particles were prepared to determine the influence of the size of the diamond particles on this process. The composites were obtained via mechanical alloying. Annealing shows that the outcome is different for cases of contact with diamond nanoparticles and microparticles. Differential scanning calorimetry has shown that the reaction between the components to produce aluminum carbide starts at 400°C to 450°C in composite materials made of aluminum and nanodiamond reinforcing particles with a size of 4 to 6 nm. The reaction with diamond microparticles starts at higher temperatures. The studies have shown that the temperature range for the use of composites with an aluminum matrix and nanodiamond reinforcing particles does not exceed 450°C.

2D Computational-Numerical Hardness Comparison between Fe-Based Hardfaces with WC-Co Reinforcements for Integral-Differential Modelling

Current industrial-hardface reinforcements presentdiverse geometrical shapes, reinforcement-particle size, chemicalcompounds proportions, volume-spatial-distribution, and chemicalcomposition—several kinds of manufactured material types orrecycling ones. Functional Erosion Models, namely, Integral-Differential Models, implement hardness spatial-distributionfunctions to determine accurately the erosion wear magnitude alongthe hardface [Casesnoves, 2016-7]. In previous contributions,several models were simulated/optimized in erosion impact wear overthese hardness differentiable functions—with separated mathematicalanalysis for matrix and reinforcement. This research is focused onextent numerical-computational comparison between two types ofreinforcements manufactured with the same hardface matrix andmanufactured with equal alloy substrate. The simulations, based onlarge laboratory data, are performed from hardface hardness part-distributions to complete/total hardface hardness plottings.Programming software was developed in two kinds of compilators,that is, Freemat and Matlab. Results involve both numerical anduseful graphical determinations for further modellingimplementation. Practical engineering conclusions for erosionfunctional algorithms and accurate tribological models, andrecycling engineering industry, are obtained from the study.

Fabrication of Ceramic Reinforcement Aluminium and Its Alloys Metal Matrix Composite Materials: A Review

This paper emphasizes a summary of work on Fabrication of Aluminum and its alloy Metal Matrix Composites reinforced with different typical Ceramic powder materials. Today Aluminum and its alloys Metal Matrix composites have prominent demand in the Automobile, Aerospace and Nuclear industry due to its physical and mechanical properties appropriately. In current Scenario there are numerous fabrication processes but Stir casting is the most favorable due to its Simplicity, Flexibility and applicable to mass production with cost effective. Further Stir casting assisted with other process like electromagnetic generation device, Ultrasonic device, Heat treatment (T6), forming process, sintering etc. to refine the grains and also studied the effect of particle Size and percentage of reinforcement on mechanical properties like Hardness, Tensile strength and Lower the percentage ductility of Composite Materials.

Synthesis, Characterization and Mechanical Properties of AA7075 Based MMCs Reinforced with TiB2 Particles Processed Through Ultrasound Assisted In-Situ Casting Technique

AA7075/TiB2 composites have been synthesized through both in situ salt-melt reaction method and ultrasound assisted in situ process. Microstructural studies reveals that ultrasound assisted in situ method improves the dispersion of TiB2 particles and reduces the porosity level. Moreover, the ultrasonic treatment refines the reinforcement particle size along with improvement in particle dispersion. The mechanical property assessment confirms that ultrasonic treatment improves the mechanical properties of composite. The hardness of the AA7075 alloy is increased from 55 HV to 74 HV by the addition of 5% TiB2 particles and it further increased to 82 HV by ultrasonic treatment. A similar trend is also observed when weight percentage of particles increases to 7.5%. Addition of 5% in situ TiB2 particles increases the ultimate tensile strength of AA7075 alloy by 60 MPa and it is further enhanced by 80 MPa upon ultrasound assisted process. Composites have shown a small reduction in ductility when compared to un-reinforced alloy, though 81% ductility of matrix alloy has been retained. Similar trend has been observed in composites fabricated using ultrasonic assisted casting.

B4C-Al Composites Fabricated by the Powder Metallurgy Process

Due to the large thermal neutron absorption cross section of 10B, B4C-Al composites have been used as neutron absorbing materials in nuclear industries, which can offer not only good neutron shielding performance but also excellent mechanical properties. The distribution of B4C particles affects the mechanical performance and efficiency of the thermal neutron absorption of the composite materials. In this study, 15 wt % B4C-Al and 20 wt % B4C-Al composites were prepared using a powder metallurgy process, i.e., ball milling followed by pressing, sintering, hot-extrusion, and hot-rolling. The yield and tensile strengths of the composites were markedly increased with an increase in the milling energy and the percentages of B4C particles. Microstructure analysis and neutron radiography revealed that the high-energy ball milling induced the homogeneous distribution of B4C particles in the Al matrix and good bonding between the Al matrix and the B4C particles. The load transfer ability and mechanical properties of the composites were consequently improved. The results showed the high-energy ball milling process is an appropriate fabrication procedure to prevent the agglomeration of the reinforcement particles even if the matrix to reinforcement particle size ratio was nearly 10.

Reinforcement size effects on the abrasive wear of boron carbide reinforced aluminum composites

The use of ceramic nanoparticle reinforcements has shown significant promise for enhancing the mechanical properties of metal matrix composites due to the high specific surface area and superior intrinsic mechanical properties of nanoparticles. In this study, the effect of B4C reinforcement particle size on the abrasive wear behavior of Al-B4C composites was investigated. Composites with a homogenous dispersion of micrometric-B4C, submicron-B4C, and nano-B4C in a nanostructured Al alloy 5083 (AA5083) matrix were fabricated using cryogenic mechanical alloying and dual mode dynamic forging. Hardness was seen to increase with decreasing B4C reinforcement size, with the Al-nanoB4C composite exhibiting a 56% enhancement over unreinforced AA5083. The abrasive wear resistance of the Al-nanoB4C composite was 7% higher than the unreinforced AA5083. The other Al-B4C composites exhibited equivalent or reduced abrasive wear resistance as compared to AA5083. Analysis of the abrasive wear scars demonstrated that larger B4C reinforcements are prone to particle pull-out, thereby negating the benefit of higher hardness. The Al-nanoB4C composite has superior wear resistance due its high hardness and greater interfacial area, which hindered pull-out of nano-B4C particles.

In situ Synthesis of Al-Cr/Al Composites and Bending Property

Al-Cr/Al composites were fabricated by ultrasonic vibration assisted. Then the reinforced phase were characterized by XRD and EDS, the reinforcement particle size, morphology and distribution were observed by the use of SEM, and studied on the bending property of the composite material. The result shows that, Al and Cr generate inter-metallic compounds of Al0.983Cr0.017, Al5Cr, -Al8Cr5, -AlCr2, etc. The enhance particles, appear irregular polygonal shape, smaller particles diameter, distribute in the matrix uniformly. And the enhance particles and the matrix get good bond, clean interface, non-pollution. The bending strength bb of the composites is decline as increasing Cr content. It is easy to form stress concentration at the interface. Inter-metallic compounds grain are not easy to slip under external load force, reinforcing particles and the matrix are easy to suddenly fall off, so, composites have a greater brittle.

Processing and strengthening mechanisms of boron-carbide-reinforced aluminum matrix composites

Boron-carbide-reinforced aluminum matrix composites are widely used as various function materials. This paper aims at reviewing theoretical and experimental background related to boron-carbide-reinforced aluminum matrix composites. The powder milling processing, solid sintering, thermo-mechanical processing and the effects of reinforcement particle size on the microstructure and morphology evolution of the aluminum matrix composites are reviewed. The formation of interface between boron carbide and matrix and strengthening mechanisms of the boron-carbide-reinforced aluminum matrix composites are discussed.

Influence of Reinforcement Parameters and Ageing Time on Mechanical Behavior of Novel Al2024/SiC/Red Mud Composites Using Response Surface Methodology

This study investigates the mechanical behavior of aluminum 2024 matrix composites reinforced with silicon carbide and red mud particles. The hybrid reinforcements were successfully incorporated into the alloy matrix using the stir casting process. An orthogonal array based on Taguchi’s technique was used to acquire experimental data for mechanical properties (hardness and impact energy) of the composites. The analysis of variance (ANOVA) and response surface methodology (RSM) techniques were used to evaluate the influence of test parameters (reinforcement ratio, particle size and ageing time). The morphological analysis of the surfaces (fractured during impact tests) was conducted to identify the failure mechanism. Finally, a confirmation experiment was performed to check the adequacy of the developed model. The results indicate that the ageing time is the most effective parameter as far as the hardness of the hybrid composites is concerned. It has also been revealed that red mud wt.% has maximum influence on the impact energy characteristics of the hybrid composites. The study concludes that Al2024/SiC/red mud hybrid composites possess superior mechanical performance in comparison to pure alloy under optimized conditions.

Effect of weight fraction and particle size of CRT glass on the tribological behaviour of Mg-CRT-BN hybrid composites

Abstract The current research focuses on dry sliding wear behaviour of end of life CRT panel glass and BN reinforced hybrid magnesium matrix composite fabricated through powder metallurgy route. CRT panel glass percentage (5, 10 & 15 wt %) and particle size (10, 30 & 50 μm) are varied to find its effect on wear performance and BN solid lubricant is added at a fixed level of 2%. Increase in reinforcement content and particle size decreases the wear rate whereas the opposite trend is found for coefficient of friction. ANOVA results reveal that all of the considered parameters significantly influence the response parameters. Taguchi based GRA is used for multi objective optimization and the worn surface SEM analysis is also performed.

Mechanical performance of particulate-reinforced Al metal-matrix composites (MMCs) and Al metal-matrix nano-composites (MMNCs)

The metal-matrix composites/nano-composites (MMCs/MMNCs) reinforced with hard ceramic particulates have received a tremendous attention due to their potential improvements in physical and mechanical performances. In the present work, we have comprehensively collected currently available experimental data sets of Al-based MMCs/MMNCs and have carried out thorough analyses to quantitatively address the impacts of the reinforcement volume fractions, reinforcement particle sizes, and metal-matrix grain sizes on their mechanical properties including the yield strength, ultimate strength, and strain to failure of composites. We also performed a quantitative analysis on the strengthening mechanisms of Al MMNCs to reveal that the grain refinement can play a major role in increasing the strength of composites. Al-based MMC or MMNC materials generally exhibited an indirect relationship between the strength increase and strain-to-failure increase. The results include a critical comparison for the mechanical performance of particulate-reinforced composites for both pure and alloyed Al matrices to elucidate the contemporary status of Al MMC and MMNC materials.

New porous Mg composites for bone implants

Various porous Mg alloys and composites have been fabricated to date. However, typically they have unsatisfactory mechanical properties, particularly in load bearing applications. In the current work, porous magnesium-niobium (Mg-Nb) and magnesium-tantalum (Mg-Ta) composites were fabricated via a combination of mechanical milling and powder metallurgy processes. The effect of Nb and Ta contents on the porosity, pore size and mechanical properties of the porous Mg composites was investigated. The microstructural observations show irregular cell shapes, including micro- and macro-pores in the porous materials. The number and size of macro-pores increased with an increase in the amount of reinforcement (Nb or Ta). The mechanical properties of the porous Mg composites increased with an increase in reinforcement contents up to 2 wt% and then decreased. The type, particle size and position of reinforcements influence the strength of porous composites. Fractography of the compressed porous samples showed that in porous Mg-Nb and Mg-Ta composites, cracks are initiated from pores and gaps between Mg powders and propagated through cell walls and cell edges. The strength of these porous Mg composites is comparable to that of human bone.

Experimental investigation and FE simulation of spherical indentation on nano-alumina reinforced copper-matrix composite produced by three different techniques

Preparation of metal matrix composites with homogenously distributed reinforcement is a difficult process. The process can be even more complex when the reinforcement particles are nano-particles. In this paper, three different techniques (dry mixing, mechanical alloying and mechanochemical) were applied to produce Cu-Al2O3 nano composite with three different Al2O3 content (2.5, 7.5 and 12.5.wt.%). XRD, SEM and EDX analysis were conducted to analyse the physical and structural properties of the produced samples. Rockwell hardness test and compression test were applied to determine the mechanical properties of the produced composites. A 2D axisymmetric FE model was implemented using commercial software to predict the Rockwell hardness of the prepared samples. The results show that dry mixing and mechanical alloying techniques are valid for production of metal matrix composites with large reinforcement particle size and low reinforcement content. However, mechanochemical technique can be used to produce Cu-Al2O3 nano composite with high reinforcement weight fractions. Homogenously distributed dispersed nano alumina copper matrix can be achieved by applying mechanochemical technique and as a result, the mechanical and physical properties can be improved. The hardness predicted by the presented FE model correlates well with the experimental observation.

Contribution of machining to the fatigue behaviour of metal matrix composites (MMCs) of varying reinforcement size

The high cycle constant stress amplitude fatigue performance of metal matrix composite (MMC) components machined by a milling process was investigated in this study as a function of machining speed, feed rate and reinforcement particle size. The presence of reinforcement and particle size were found to be the most influential factors that affected the fatigue life. In contrast to this, the effect of feed and speed on tool-particle interaction, strain hardening and heat generation during milling of MMCs were balanced in such a way that the contributions of feed and speed on fatigue life were negligible. The interactions of different parameters contributed significantly to the fatigue life which indicated that the modelling of fatigue life based on these three parameters was relatively complex. The fatigue life of the machined MMC samples increased with decreasing particle size and increasing feed. However, the fatigue life was not influenced by speed variation. The presence of smaller or no particles induced a complete separation of failed samples, in contrast to that of specimens containing larger reinforcing particles where crack growth was arrested or deflected by the reinforcing particles.

On modeling tool performance while machining aluminum-based metal matrix composites

Tool performance while machining aluminum-based metal matrix composites has been investigated by developing finite element models based on particle size and volume fraction of the workpiece. Two types of finite element models are developed, i.e., with and without cohesive elements. The effects of varying cutting speed, feed rate, volume fraction, and size of reinforcement particles on tool performance are investigated using both models. It has been found that models without cohesive zone element can predict cutting forces, tool stresses, and temperatures to a reasonable degree of accuracy. The increase in tool stresses and temperatures due to cutting speeds, feed rate, particle size, and volume fraction can be visualized with these models. Models based on cohesive elements can predict localized effect of particle debonding and failure on tool stresses and machined surface. It has been noticed that increase in particle size and cutting speed increases the effects of particle rolling and sliding on the tool face due to increase in kinetic energy resulting in high wear.

Effect of Particle Size of B4C Reinforcement on Ti-6Al-4V Sintered Composite Prepared by Mechanical Milling Method

ABSTRACTIn this study Ti, Al, V and B4C powders were milled separately in ball mill for various time periods. The powder morphology was tested by particle size analysis (PSA), FTIR and SEM studies in every one hour interval. Finally the individual powders were mixed on a weight basis to produce novel Ti-6Al-4V-B4C composite precursor and fabricated compacts were heat treated at 900°C. The microstructural features and mechanical properties of the sintered compacts were ascertained by microhardness and SEM studies. It was observed that with increase in milling time and B4C reinforcement of 10 wt% yields a significant improvement of microhardness as well as homogeneous microstructure in the sintered composite.

Machinability of Hybrid Metal Matrix Composite - A Review

Aerospace and automotive industries are eager on introducing hybrid metal matrix composites in their components due to their excellent mechanical and physical properties, leading to reduction in the weight of structural components and energy requirement for propelling. Components made by hybrid metal matrix composite (based on Aluminum alloy reinforced with single wall and multi wall carbon nanotubes, Graphene and ceramic particles) required secondary operations to enhance the dimensional tolerance and surface finish. Machining operations generally requires minimum tool wear rate and good surface finish with lowest energy requirement. Hard metal, ceramic and oxide reinforcements in the composite increase the tool wear and machining cost. To improve tool life and increase the metal removal rate significant care is needed for the selection of optimum cutting parameters and cutting conditions. This review focuses on the influence of reinforcement particle's types, shape, size and volume fractions on the machinability issues like the cutting force, tool wear, chip formation and surface roughness. Further, the role of various cutting parameters like cutting speed, feed, depth of cut and tool material, tool geometry and cutting conditions during turning of hybrid metal matrix composites are critically reviewed.

Influence of large particle size – up to 1.2 mm – and morphology on wear resistance in NiCrBSi/WC laser cladded composite coatings

This paper aims at studying the influence of the reinforcement particle size and morphology on the wear resistance properties of NiCrBSi-based composites. Numerous papers have already been written on this subject but almost all of them studied the “conventional” particle size for laser cladding (i.e. between 20 and 200μm). The objective of this study is to see the influence of coarser reinforcement particles, up to 1.2mm, and the influence of the morphology (spherical and random shaped) on the coatings erosive and sliding wear resistance. Laser clad coatings were deposited on low carbon steel substrate S235JR with various amounts of WC/W2C particles up to 50vol.%. The coatings were processed by using a 3.8kW High Power Diode Laser (HPDL). Spherical tungsten carbide particles from 40μm up to 1200μm were used in this study as well as random shaped particles from 40μm to 400μm. To assess the influence of the reinforcement particle properties on wear properties, wheel tests and pin-on-disk tests were performed on each composition. From this study, it can be concluded that there is an obvious advantage in using larger particles (750–1200μm) in harsh conditions while smaller particles (40–160μm) improve the resistance in sliding conditions. The effect of morphology has not been proved significant.

Effect of Particle Size on Microstructure and Mechanical Properties of Al-Based Composite Reinforced with 10 Vol.% Mechanically Alloyed Mg-7.4%Al Particles

The effect of Mg-7.4%Al reinforcement particle size on the microstructure and mechanical properties in pure Al matrix composites was investigated. The samples were prepared by hot consolidation using 10 vol.% reinforcement in different size ranges, D, 0 < D < 20 µm (0–20 µm), 20 ≤ D < 40 µm (20–40 µm), 40 ≤ D < 80 µm (40–80 µm) and 80 ≤ D < 100 µm (80–100 µm). The result reveals that particle size has a strong influence on the yield strength, ultimate tensile strength and percentage elongation. As the particle size decreases from 80 ≤ D < 100 µm to 0 < D < 20 µm, both tensile strength and ductility increases from 195 MPa to 295 MPa and 3% to 4% respectively, due to the reduced ligament size and particle fracturing. Wear test results also corroborate the size effect, where accelerated wear is observed in the composite samples reinforced with coarse particles.

Modeling and Analysis on the Influence of Reinforcement Particle Size During EDM of Aluminum (Al/3.25Cu/8.5Si)/Fly Ash Composites

In the present study, aluminum alloy (Al/3.25Cu/8.5Si) composites reinforced with fly ash particles was fabricated using stir casting technique. Fly ash particles of three different size ranges 53–75, 75–103 and 103–125[Formula: see text][Formula: see text]m of 3, 6 and 9 weight percentages was reinforced in aluminum alloy. The effect of peak current, pulse on time, and pulse off time on surface roughness (SR), material removal rate (MRR) and tool wear rate (TWR) of electric discharge machining (EDM) was investigated. A central composite design using response surface methodology (RSM) was selected for conducting experiments, and mathematical models were developed using Design Expert V7.0.0 software. Analysis of variance (ANOVA) technique was used to check the significance of the models developed. Peak current was the major factor influencing the EDM of aluminum fly ash composites. The MRR, TWR, and SR of aluminum fly ash composites were also influenced by the size of the fly ash particles.