Al-based Metal Matrix Composites Research Articles

Empirical investigation on controlled porosity level and dry sliding wear behavior of Al7075-(T6) doped with SiC+MoS2 based hybrid composites via advanced vacuum-assisted stir casting

This paper investigated Al-based hybrid metal matrix composites (HMMCs) comprised of Al7075-(T6) base metal matrix doped with SiC+MoS2 reinforced particles for high-strength, lightweight, and wear-resistant applications. Taguchi’s design of L9 orthogonal array (OA) with three process variables having different levels (such as SiC particle (2.5, 3.5, and 4.5 wt.%), MoS2 particle (1.5, 2.5, and 3.5 wt.%), and stirring speed (580, 600, and 620 rpm)) has been selected for fabrication of Al-based HMMCs via an advanced vacuum-assisted stir casting route. The controlled porosity level and dry sliding wear behavior (i.e. wear loss) of fabricated hybrid composites at an ambient temperature of 35°C have been conducted. Besides, metallographic evaluation was inspected through optical microscopy, high-resolution FESEM, and SEM-EDS techniques. Furthermore, experimental outcomes obtained from Taguchi’s design of experimentation were optimized by analysis of variance (ANOVA); and also validated through an artificial neural network (ANN) modeling with a network topology of 3-10-2. The results concluded that a homogeneous dispersion of reinforced particles over the base metal matrix (with controlled both abrasive and adhesive wear mechanisms of worn surfaces). Moreover, a significant reduction in porosity level (up to 29.41%) and wear loss (up to 4.94%) of the proposed hybrid specimen (S4) as compared with an unreinforced specimen (S0). In addition, the predicted values obtained from the ANN model were confirmed in close proximity to Taguchi’s experimental outcomes (with less percentage error), which in turn certified the authentication of the constructed ANN model for the Al-based HMMCs.

Thermophysical properties of Al-based metal matrix composites suitable for automotive brake discs

The present work investigates the effects of Ni, Cu, La, and Ce on the thermophysical properties of aluminium-based metal matrix composites. Transition metals and rare-earth elements were added to improve the mechanical performance of the material to above 420 °C, which is the maximum operating temperature of the reference material. In contrast, the addition of alloying elements results in the formation of intermetallic phases, Al3Ni and Al11(La,Ce)3, which, in turn, affect the thermal and physical properties of the base alloy. The goal is to apply the improved composites to automotive brake discs. The addition of alloying elements decreased the thermal conductivity by 20% and increased the stiffness by 90% at temperatures up to 470 °C. When stiffness and thermal conductivity are critical requirements, the addition of these alloying elements represents a valid solution.

Influence of SiO2 and nano graphene particles on the microstructure and mechanical behavior of A356 alloy metal composites

The current research focuses on investigating the microstructural and mechanical properties of aluminum (Al) metal matrix composites (MMCs) reinforced with both silicon dioxide (SiO2) and nano-graphene particles. The composite material was produced using a novel two stage stir cast metallurgy approach. In this study, a constant reinforcement of 1 wt. % nanographene was maintained, while the SiO2 content was independently varied at levels of 2.5, 5, and 7.5 wt. %. Employing scanning electron microscopy (SEM) tool, microstructural analyses were conducted, revealing a uniform dispersion of ceramic silicon dioxide (SiO2) and graphene particles within the as-cast A356 MMCs. Mechanical testing, following the ASTM standards, was carried out on the composites, specifically assessing tensile strength, yield strength, and percentage elongation to evaluate the properties of the Al-based MMCs. The findings of this study indicate a significant enhancement in both tensile and yield strength values for the fabricated composites by 60.64% and 82.78% respectively. However, it is important to note that the percentage elongation decreases as the reinforcement content in the composite increases.

Grey relational analysis and surface texture analysis of Al-based metal matrix composites

The investigation found that the incorporation of MoS2 particles as reinforcement in Al–4% Mg material results in an increase in density and microhardness. The composite with 4% Mg and 6% MoS2 exhibited the highest percentage increase in the density up to 8.04%, and the highest percentage increase in the microhardness value of up to 33% as compared to the pure Aluminium. The pin-on-disc wear test revealed that the wear loss of the Al–Mg alloy is reduced by adding MoS2 particles as reinforcement. The wear loss decreases by 16.03% for the composite with 4% Mg and 6% MoS2. SEM analysis showed that the composite with higher MoS2 content (6%) exhibits a smoother worn surface. However, WEDM machining of the composite materials at higher levels of peak current, pulse on time, and gap voltage resulted in poor surface quality with more craters and micro voids. The sliding distance (m) was found to be the most significant parameter for wear output parameters, contributing to 57.05%–59.08% of the materials in samples 1 to 5. Similarly, the pulse on time (μs) was the most significant parameter for WEDM output parameters, contributing 46.29%–80.33% for the materials in samples 1 to 5. The study concluded that the PM route is an effective method for producing Al–Mg–MoS2 composites, which can improve the wear resistance of the Al–Mg alloy, and that WEDM parameters need to be optimized to achieve a better surface finish.

Application of metal matrix composite fabricated by reinforcement materials – A review

Metal Matrix Composites (MMCs) are recently developed fabricated materials with characteristics like reduced thermal expansion coefficient, enhanced specific strength, improved wear resistance, and light in weight. They contain feature such as low density, good strength-to-weight ratio, lightweight, low cost, excellent quality, and high performance. Among others, Aluminium (Al) and Al alloy based MMCs are employed in a variety of industrial applications. The characteristics of the composite are greatly influenced by the Al-based MMC fabrication processes. The manufacturing processes for reinforced composites as well as contemporary fabrication techniques are reviewed in present article. The impact of various process factors on the characteristics of aluminium based MMC has also been discussed. Various techniques such as powder metallurgy, stir casting, hand lapping etc. are utilized for the fabrication of composites. The primary objective of the present work is to review different fabrication methods of Al MMCs along with their features. This article also deals with changes occur in mechanical and physical properties with fabrication methods. The effects of the addition of different reinforcement have also been discussed in the present work. Investigation of mechanical and microstructure properties have also done in this paper. The main purpose of this review is to find effect of fabrications process on different properties of fabricated material as well as finding of suitable method of fabrication.

Correction to: Effect of SiC on Mechanical Properties of Al-Based Metal Matrix Composites Produced by Stir Casting

Correction to: Effect of SiC on Mechanical Properties of Al-Based Metal Matrix Composites Produced by Stir Casting

Data-driven analysis in magnetic field-assisted electrical discharge machining of high-volume SiCp/Al

This paper presents a framework of data-driven intelligence system which can be applied on magnetic field-assisted electrical discharge machining (MF-EDM) machining process for SiC particulate reinforced Al-based metal matrix composites (SiCp/Al) with different high-volume fractions. The implemented system consists of data modelling, predicating, optimization and monitoring modules. A multi-objective moths search (MOMS) optimization algorithm with backpropagation neural network (BPNN) model and multi-hierarchy non-dominated strategy is proposed for tuning optimal processing performance. Data are collected from machining different fraction volumes of SiCp/Al composites by MF-EDM, with peak current, magnetic, pulse width and pulse interval time as input, and material removal rate, electrode wear rate, surface roughness as output. The BPNN model shows the best accuracy compared to K-nearest neighbors, least square support vector machine and Kriging model. To demonstrate the effectiveness of the MOMS optimization algorithm, a set of results is selected as paradigm, which dominates 95.83% original experiments. A verification experiment is also done for an optimized parameter with 65% fraction and 0.2T magnetic. Both result data and three-dimensional surface topography comparison show that the verification experiment result dominates the original experiment of similar input designs.

Effect of SiC on Mechanical Properties of Al-Based Metal Matrix Composites Produced by Stir Casting

Effect of SiC on Mechanical Properties of Al-Based Metal Matrix Composites Produced by Stir Casting

Enhanced hardness and wear resistance of Al-based hybrid MMCs by using of composite metal boride reinforcement particles

Composite metal boride particles were synthesized and then used as the reinforcement material for fabricating Al-based hybrid metal matrix composites (MMCs). Mechanical alloying and pressureless sintering methods were used to produce the Al - 2 wt % Co–Ni–B/Co–Ti–B hybrid composites. Mechanically alloyed powders and sintered composites were characterized in terms of physical, microstructural and mechanical properties. The low crystallite size of Al particles and high density of the composites provided improved microstructures without needle-shaped secondary phases, and increased nanohardness values of Al matrix, and hence resulted in enhanced mechanical properties. The lowest indentation depths (both for matrix and reinforcement phases), the highest hardness (∼2 GPa) and the lowest wear volume loss (∼0.13 mm3) were obtained from the Al-based MMCs reinforced with Co–Ni–B particles containing CoB and Ni2Co0.67B0.33 phases. Studies revealed that the synergetic effect of the binary and ternary boride phases in the composite reinforcements had a positive role on the hardness and wear resistance of hybrid composites.

Temperature dependence of Young’s Modulus of alumina short fiber reinforced Zn–Al MMCs produced by pressure die-casting

Abstract Conventional pressure die-casting was used to produce δ-Al2O3 (Saffil) short fiber reinforced Zn–Al based metal matrix composites, containing 10, 15, 20, 25 and 30 vol.% fibers. The temperature dependence of the elasticity modulus of the composites and the matrix material were measured at temperatures from 20 to 200 °C, at 20 °C intervals. It was found that the modulus of elasticity of the composites gradually increased with increasing fiber volume, but decreased with increasing temperature. The rate of change in both, however, differed depending on the fiber volume content of the composites in such a manner that the higher the volume content of fibers the lower the rates of decrease in the modulus of elasticity values with increasing fiber volume and temperature. In addition, the data obtained from the Young’s modulus measurements over the temperature range studied were compared with theoretical results predicted by the shear-lag and Nielsen–Chen models and found to be in a better agreement with those of the later model.

WEDM Machining Performance of Al Based Metal Matrix Composites Reinforced with Rice Husk Ash

With the enhancement in science and technology, necessity of complex shapes in manufacturing industries becomes essential for more versatile applications. These lead to demand for light weight and durable materials for applications in aerospace, defence, automotive, as well as sports and thermal management. Due to its high-tech structural, functional applications like defence, automobile, aerospace, thermal sensitive materials. Al-Matrix composites are considered as one of those classes of advanced engineering materials. In the present study, Al-RHA (Rice Husk Ash) composites are prepared by powder metallurgy route using 10% and 15% RHA by weight as reinforcement. Presence of abrasive particles leads to difficulty of conventional machining on Al-RHA composites hence non-conventional machining WEDM (Wire-Electric Discharge Machining) has been investigated. Suitable machining parameters for composites using wire EDM have been tried to get maximum material removal rate and speed. Optimizations of experimental parameters have been studied using Taguchi and Anova to standardize the process parameters for machining. Prime process parameters like servo-voltage, pulse-on time and pulse-off-time have been taken into consideration to study cutting quality of Al-RHA Metal matrix Composite using cutting speed as response parameters while effect of RHA weight fraction addition is also considered for evaluation to understand its influence on affecting the response.

Effect of reinforcement on microstructure and mechanical properties of aluminium hybrid composites

Al based metal matrix composites are widely used in aerospace and automobile and engineering applications where high strength to weight ratio and good corrosion resistance are of prime importance. In the present investigation SiC/Al2O3 and SiC + Al2O3 particulate reinforced metal matrix composites with varying weight percent of SiC, Al2O3 and SiC + Al2O3 (2,4,6) were produced by a stir casting process. An optical microscope was used to examine the morphology of dendrites and distribution of reinforcement at varying magnification. The porosity content was measured by comparing the theoretical and experimental determined by Archimedean method. Bulk (Brinell hardness test) and Micro(Vickers Hardness test)hardness tests were done. Brinell hardness test has advantage of covering larger area and hence it incorporates all microstructural heterogeneity whereas microhardness gives information abour interface bonding strength between reinforcement and matrix. The results indicated that in case of SiC reinforcement, there is increase in porosity with increase in wt. % of SiC particles and in case with Al2O3 exceptionally high porosity (%) with 4 wt% Al2O3 due to error during casting. However, in case of hybrid (SiC + Al2O3) composite there is increase in microhardness, Brinell hardness, compared to unreinforced A356 alloy and mono composites.

Wear behavior analysis of aluminium composites using Taguchi approach

Every industry, particularly the automotive and aerospace industries, has a constant need for exceptional materials. Aluminium is the most often utilized material in these sectors. Despite the fact the it contains all of the features to some level, there is a continuing desire for alternative materials. In the automotive industry, friction stir welding represents a huge step forward. In this present study, Stir casting was used to manufacture Al-based metal matrix composites with 9% of TiC particles and 2% of MoS2 as reinforcement. The applied force, sliding velocity, and sliding distance are used as input parameters, while the wear rate is the response. The L27 orthogonal array of Taguchi technique is used to study the relevance and contributions of factors on wear behavior and a statistical plot are used to determine the connection between parameters. Weight percentage of TiC and MoS2 are found to be the most contributing parameter to minimize the wear rate (30.12×10-6mm3/m). Furthermore, sliding velocity and applied load are observed to be the reasons for the increment of wear rate of the optimum composite. Statistical plots are verified that the travel distance is the influencing parameter to minimize the wear rate.

Compressive behavior of CNT-reinforced aluminum matrix composites under various strain rates and temperatures

Carbon nanotubes (CNTs) have been attractively used as reinforcement in metal matrix composites (MMCs) for advanced mechanical properties. However, the effects of loading rate and temperature on such materials are still to be resolved. In the present study, aluminum-based MMCs reinforced with CNTs of different contents were investigated under various loading rates and temperatures, along with microstructural examination by electron microscopy. It is found that the strengthening capability of CNTs/Al in comparison to PBM Al decreased with the temperature increasing and loading rate decreasing. However, microstructure characterization showed that CNTs played an essential role on hindering dislocation movement and stabilizing the microstructure, thus yielding an increased strength in Al-based MMCs at temperatures up to 603 K, regardless of the loading rate. A constitutive model that takes into the effect of temperature and microstructures account is then established to illuminate the role of CNTs. In addition, experimental results showed that the CNTs-reinforced Al composites exhibited an enhanced value of strain rate sensitivity and a reduced activation volume than the Al counterpart under all the tested temperatures. It is also found that the increased temperature softened the matrix and reduced the amounts of interactions of mobile dislocations with CNTs and forest dislocations, which led to the enhanced thermal activation volume of the CNTs/Al with temperature.

Influence of coarse grain particles on mechanical properties and fracture behavior in multi-modal Al-based metal matrix composites

We reported the fracture behavior of multimodal AA7075-B4C composites with three types of coarse grains (CG, AA7075 powder-1 μm, AA7075 powder-10 μm, and as-cryomilled AA7075 powder) synthesized via cryomilling and plasma activated sintering. Our results indicated that the type (particle size) and weight fraction could affect the distribution of CGs, which in turn significantly affect the fracture behavior of multi-modal composites. Multiple voids were found in the vicinity of AA7075 powder-1 μm, leading to a limited plasticity even with a lower yield strength. AA7075 powder-10 μm (25%) could distribute homogeneously in the composites, resulting in a high yield strength (712 ± 24 MPa) with the plasticity of ~7.7%. The localized grain growth occurred during consolidation with addition of as-cryomilled AA7075 powder. Noted that once the continuous distribution of CGs were detected in the composites, the yield strength decrease dramatically. The CGs could enhance the plasticity by retarding the propagation of micro-cracks during deformation.

WITHDRAWN: Developments in sintered aluminium based composites

Sintered aluminium (Al) based composites are providing unique properties in the present day manufacturing sectors when compared to traditionally used structural materials. From past decades there is a tremendous research for conventionally developed composites and there is a vast insight for conventional ones rather than sintered based composites. The objective of this work is initiated due to the rapid growth in the sintering science and methodology. An attempt is therefore made to develop substantial interest for producing a new class of composite materials through sintering route. The parameters that influence these composites and their applications in various fields have remarkable attention too. Whereas, limited studies have mentioned the effect of those factors that influence structural refinement, porosity and mechanical properties in the sintered composites. Hence, the present paper focuses on the unexplored data and information pertaining to recent developments in sintered Al based metal matrix composites. A review of the latest contributions in the microstructure, mechanical and other properties of sintered Al is also presented so as to guide future researchers.

Additive Manufacturing of Aluminum‐Based Metal Matrix Composites—A Review

Al‐based metal matrix composites (AMMCs) have found enormous applications in the aerospace, automobile, and other structural applications. Compared with the conventional processes such as casting and powder metallurgy, AMMCs processed by additive manufacturing show a significant difference between microstructure and properties. This work presents the achievements of AMMCs fabricated by additive manufacturing in recent years, which is divided into six sections. Starting with the introduction, this work focuses on different fabrication methods such as composite powders and bulk material production. This is followed by discussing the microstructure in relation to the typical reinforcements and matrices, interface, and defects, and emphasizes the advantages and disadvantages compared with the unreinforced counterparts. The fourth part summarizes the recently obtained mechanical properties and the fifth part discusses the possible strengthening mechanisms and their connection with the mechanical properties. The last part is devoted to concluding the advantages, limitation, and outlook of the additively manufactured AMMCs. This review will provide a comprehensive picture of the processing–microstructure–property‐strengthening mechanisms correlation of these composites.

Synthesis and electrochemical behaviour of TiC- and B4C-reinforced Al-based metal matrix composite

Aluminium (Al)-based metal matrix composites were developed with titanium carbide (TiC) and boron carbide (B4C) materials as reinforcement. The weight percentages of titanium carbide (1.5%) and boron carbide (0.5%) powder were maintained throughout the process of composite development. Composite process parameters such as powder compaction pressure, sintering temperature and time were varied in different combinations. The prepared composites were mechanically evaluated and metallurgically investigated for their quality. Further, the samples were subjected to electrochemical analysis to study their behaviour in 3.5% sodium chloride (NaCl) solution. From the experimentation, the corrosion potential and current density were measured. Subsequently, the corrosion rate (mm/year) of the material was calculated through its Tafel plot. The composite processed at a sintering temperature of 630°C for a duration of 135 min had higher corrosion resistance, with a minimum corrosion rate of 1.699 mm/year. The electrical resistance also increased over the exposed surface with a minimum current density of 0.15 mA/cm2. Scanning electron microscopy and energy-dispersive spectroscopy (EDS) were used to determine the metallurgical quality of the exposed surface. The oxide formation was observed on the exposed surface in the process of corrosion. The element aluminium and oxygen were found on the surface which denotes that the Aluminium oxide formed on the exposed surface. From the results, a discussion is presented confirming the influence of composite powder processing parameters.

Study on productivity and aerosol emissions of magnetic field-assisted EDM process ofSiCp/Alcomposite with high volume fractions

SiC particulate reinforced Al-based metal matrix composites with high volume fractions ( HVF − SiC p / Al ) is widely applied in many engineering fields due to combining outstanding properties of both metal and ceramic materials. It’s a tough problem to process HVF − SiC p / Al with superior machining performance and minor environmental effect. Thus, in this paper, magnetic field assisted electrical discharge machining (MF-EDM) of HVF − SiC p / Al is proposed to improve the sustainable machining performance including productivity and aerosol emissions which is most harmful to operators’ health. Based on Taguchi method, a set of experiments are settled to investigate materials removal rate (MRR), electrode wear rate (EWR), and aerosol emissions under MF-EDM process of 45% and 65% SiC p / Al . It shows that pulse current is the major factor, and magnetic field assisted technology significantly develops the surface integrity whereas it just slightly contributes to improve MRR, EWR, and aerosol emissions when the intensity of magnetic is in the range of 0.1T–0.2T. Additionally, an optimization algorithm combing Quantum-behaved Particle Swarm Optimization with Gaussian distributed local attractor (GAQPSO) and Back Propagation Neural Network (BPNN) is employed to provide optimal machining parameters for economic and environmental MF-EDM process of HVF − SiC p / Al . Compared to the average experimental data, for 45% SiC p / Al , the average optimal solutions of EWR, and aerosol emissions were decreased by about 10% and 15% whereas MRR was increased by about 6.6%; for 65% SiC p / Al , the average optimal solutions of EWR, and aerosol emissions were decreased by about 5.7% and 10% whereas MRR was increased about by 5.5%. It presents an effective work for EDM process of HVF − SiC p / Al with high sustainable performance. • Magnetic field assisted EDM of HVF-SiC p /Al is proposed to improve productivity and aerosol emissions. • Material removal rate, electrode wear rate, aerosol emissions, and surface integrity of MF-EDM were completely investigated. • The composition of emitted aerosols from MF-EDM of HVF-SiC p /Al is analyzed. • MF-EDM process of HVF-SiC p /Al is optimized economically and environmentally by BPNN-GAQPSO method. • Optimal parameter combinations for MF-EDM process of 45% and 65% SiC p /Al are recommended.

Machining performance of in-situ TiB<sub>2</sub> particle reinforced Al-based metal matrix composites: A literature review

The in-situ TiB₂ particle reinforced Al-based metal matrix composites have become a series of promising aeronautical materials due to the advanced properties such as finer evenly-distributed grains, cleaner particle-matrix interface, improved mechanical performance and strength when compared with ex-situ SiC particle reinforced Al-based metal matrix composites. However, over the last 50 years, a significant body of research has been carried out on ex-situ SiC particle reinforced Al-based metal matrix composites from material fabrication process, material property improvement, material mechanical test to machining performance such as machined surface integrity, cutting process simulation and modeling, parameter optimization and fatigue characteristics. For in-situ TiB₂ particle reinforced Al-based metal matrix composites, studies in recent years were mainly focused on the material preparation process and property development and few published works was found on the machining performance of this new kind material. Hence, this article aims to provide a general overview of recent achievement on machining performance of in-situ TiB₂ particle reinforced Al-based metal matrix composites.