Recent progress in aluminum metal matrix composites: A review on processing, mechanical and wear properties

An overview of the effect of stirrer design on the mechanical properties of Aluminium Alloy Matrix Composites fabricated by stir casting

Metal matrix composites offer a number of advantages compared to their base metals, such as higher specific strengths and moduli, higher elevated temperature resistance, lower coefficients of thermal expansion, and, in some cases, better wear resistance. On the down side, they are more expensive than their base metals and have lower toughness. The combined effect of reinforcements on Aluminium Metal Matrix composites with individual and multiple particulate reinforcements like Hybrid Metal matrix composites are finding increased applications in aerospace, automobile, space, underwater, and transportation applications. This is mainly due to improved mechanical properties like strength, stiffness, abrasion, impact resistance and wear resistance. Besides, high tensile and shear moduli, good fatigue and fracture properties, small thermal expansion coefficient, high melting point, high toughness, high ductility, high thermal and electrical conductivities, good erosion resistance, dimensional stability and good moisture resistance make reinforced Aluminium Matrix composites more attractive. In this paper an attempt has been made to provide the effect of reinforcement and also discuss the types of reinforcement used inAluminium based MMC. Reactivity of the matrix and the reinforcing material, type of the reinforcing material, volume fraction of the reinforcing material and distribution of the reinforcing material are the main challenges encountered during adding of reinforcements in the production of Aluminium Matrix Composites.Metal matrix composites offer a number of advantages compared to their base metals, such as higher specific strengths and moduli, higher elevated temperature resistance, lower coefficients of thermal expansion, and, in some cases, better wear resistance. On the down side, they are more expensive than their base metals and have lower toughness. The combined effect of reinforcements on Aluminium Metal Matrix composites with individual and multiple particulate reinforcements like Hybrid Metal matrix composites are finding increased applications in aerospace, automobile, space, underwater, and transportation applications. This is mainly due to improved mechanical properties like strength, stiffness, abrasion, impact resistance and wear resistance. Besides, high tensile and shear moduli, good fatigue and fracture properties, small thermal expansion coefficient, high melting point, high toughness, high ductility, high thermal and electrical conductivities, good erosion resistance, dimensional stability and good...

• Several new combinations of metal matrix composites have been produced in recent decades. • Aluminum composites are considered among the most advanced structural materials, classified as metal matrix composites (MMCs), due to their superior properties for automotive and aerospace applications. • Al MMCs were synthesized using different fabrication methods. The formations of stable reinforcement particles in the composites resulted in superior mechanical and wear properties for Al MMCs. • Recent advances in processing, microstructure, wear, and mechanical properties of Al matrix composites increased with innumerable types of particles are covered in this review paper. • At the end of the study, future directions for these composites will also be discussed. • These articles outline the production process and highlight the mechanical and wear properties of AMCs with various reinforcements. • A brief discussion of the advantages and limitations of different methods is provided. • The choice of a fabrication process is mainly dependent on the required quality, cost, and efficiency of the process. • The technique for improving UTS, impact resistance, and hardness has been thoroughly explored. • Orowan strengthening, along with the load-bearing effect, strongly affects the strength of the composites. • The effect of various parameters on the wearing characteristics of AMCs was also explained in detail. • The mechanisms are briefly discussed, along with relevant research papers on the wear surfaces. • This review aids in identifying the research background and challenges associated with the processing of AMCs, despite their good performance in current applications. Aluminum matrix composites (AMCs) have received attention over the past decades in the automotive and aerospace industries due to their high strength, low weight, and wear resistance. This review presents a detailed analysis of the microstructure, mechanical, and tribological properties of AMCs. It begins with the primary fabrication processes, including stir casting, liquid-state processing, squeeze casting, and solid-state processing. The review then explores the correlation between microstructural properties and processing conditions, including reinforcement distribution, phase development, porosity formation, grain refinement, and interfacial bonding. Particular attention was given to the effect of nanoparticles and hybrid reinforcement on the strengthening mechanism, microstructure, and mechanical properties of AMC. The strengthening mechanisms, Orwan strengthening, load transfer, grain boundary strengthening, and thermal mismatch were examined to explain variation in wear properties, tensile strength, and hardness. Recent advances in processing, microstructure, wear, and mechanical properties of Al matrix composites have increased, with innumerable types of particles covered in this review paper. At the end of the study, future directions for these composites will also be discussed.

Metal matrix composites (MMCs) are the emerging potential materials that have advantages over the existing materials and are suitable for many applications, viz. structural, electrical, aerospace, car, thermal and wear applications. They are far superior in terms of specific modulus, specific strength, wear resistance, chemical inertness, high-temperature stability, controlled coefficient of thermal expansion, etc. Aluminium is the most widely used metal for the matrix because of its light weight and high strength. In this chapter, boron carbide (B4C) and aluminium oxide (Al2O3) have been used as reinforcement. Boron carbide possesses high hardness value, good chemical stability, low specific gravity and high elastic modulus, making it a better reinforcing agent in a matrix material. It also has high cross-section absorption of neutrons. It possesses stability to ionizing radiation and most chemicals. Aluminium oxide is a chemical compound of Al2O3 aluminium and oxygen. It is ordinarily referred to as alumina. It has strong, ionic interatomic bonds that create highly desired material characteristics. The influence of boron carbide as well as aluminium reinforcement on aluminium MMC was analyzed in this research. Aluminium hybrid composite with 2% B4C + 1% Al2O3 and 2% B4C + 2% Al2O3 has been fabricated with stir casting method. A critical analysis of wear and mechanical properties was conducted between the aluminium 7068 alloy and the hybrid composite. Mechanical properties, viz. its tensile strength and hardness of the materials, have been assessed. The wear experiment was designed by using the Taguchi orthogonal array method. The wear test result was then optimized by using the DEMATEL method. Study of the microstructure of the composite material Scanning Electron Microscope (SEM) micrograph has been provided.

Review of recent developments in processing and application of aluminum matrix composites with alumina particles

Aluminum metal matrix composites (MMCs) find important applications in aerospace where specific stiffness is important. Low cost fly ash reinforcement is widely used in aluminium metal matrix composite due to its property of low density, high young modulus and strength apart from good mechanical and chemical compatibility & thermal stability. In the present paper the influences of weight fraction of particulate reinforcement on tensile, fracture toughness have been evaluated. The fracture toughness (KIC) of the aluminum fly ash composite increases by almost 24% that of base alloy. The load and COD plot shows hysteresis loop in loading and unloading compliance curve. This is indicative of crack closure. The reason for crack closure may be surface roughness resulting from reinforcement particles in the composites. The fracture behavior and micro-mechanism of failure in base alloy and composites have been observed under SEM and optical microscopy.

Aluminium metal matrix composites (AMMCs) are attractive and effective materials due to their tailored properties for outstanding applications, like high specific strength, lightweight, high specific stiffness, excellent wear resistance, corrosion resistance and high elastic modulus than the base metal matrix. These materials are widely used in aerospace, automobile, marine, mining and mechanical structural applications. In the present study, rock dust was considered as reinforcement particles in various wt % (2, 4, 6, 8 and 10) in aluminium material. Rock dust is a by-product of the crushing processes of rocks in the production of gravel aggregates. The purpose of this investigation is to identify the influence of rock dust reinforcements on mechanical and wear properties of aluminium-based surface composites fabricated through the Friction Stir Processing (FSP). Traverse speed, rotational speed and tool tilt angle are fixed input parameters. From the experimental results it was observed that in the fabricated composite, rock dust addition to Al material gives better wear-resistant characteristics. Enhanced trends occurred in Impact strength and micro-hardness values due to the addition of reinforcements to the aluminium material.

Aluminium Metal Matrix Composites (MMCs) are preferred to other conventional materials in the fields of aerospace, automotive and marine applications owing to their improved properties like high strength to weight ratio, good wear resistance etc. In the present work, an attempt has been made to synthesize Al6061-Al2O3particulate metal matrix composites by liquid metallurgy route (stir casting technique). Aluminium metal matrix composite was fabricated with Al6061 alloy as a matrix and Al2O3 as a reinforcement material. Reinforcement was added in the range of 0, 3 and 6 percentage by weight into the molten alloy, hence the Al6061 metal matrix composite was produced and their properties were estimated. Micro-Vickers hardness of the composite was found to increase with increase in filler content in the composite. Along with the hardness, compressive strength and the corrosion resistance properties of composite material steadily increases with the increase in the reinforcement particles in the matrix. Besides that the impact strength of composite was found to decrease with the enhancement of the ceramic reinforcement particle Al2O3 into the Al6061 alloy matrix.

Synthesis of nitrogen-doped graphene and its strengthening effect on aluminium metal matrix composite

Electrochemical behavior of a discontinuously A6092/SiC/17.5p metal matrix composite in chloride containing solution

Metal-matrix composites (MMC’s) have considerably enhanced properties including high specific strength; specific modulus, damping capacity and good wear resistance compared to non-reinforced alloys. There has been an increasing interest in composites containing low density and low cost reinforcements. Among various discontinuous dispersions used, fly-ash is one of the most less-expensive and low density reinforcement available in large quantities as solid waste by-product during combustion of coal in Thermal power plants. Alternatively Microspheres derived from the fly ash is also used as reinforcement in Aluminum Metal Matrix Composite to enhance the material properties. Hence, MMC’s uses fly ash and its derivatives used as reinforcement are likely to overcome the cost barrier for wide spread applications in automotive and other industrial applications.Similarly particulate reinforced Aluminum Metal Matrix Composite are gaining importance because of their low cost with advantages like isotropic properties and the possibility of secondary processing facilitating fabrication of secondary components. The Stir casting method based particulate reinforced Aluminum Metal Matrix Composites have higher specific strength, specific modulus and good wear resistance as compared to non-reinforced Al-alloys. They find wide applications in automobile and aerospace because of their excellent combination of physical, mechanical and tribological properties. Primarily because of their high specific strength and stiffness, these composite materials could also be used in Automobiles weight reduction and other applications. In this work a comparative study between Fly ash and Fly ash derived Microsphere base Al-MMC is explained in lucid manner.

Abrupt advancement in technologies lead to growing thirst for efficient and economical alternative materials that possess superior properties. This lead to a gradual shift from the use of monolithic alloys to Metal Matrix Composites (MMCs). High resistance to corrosion and wear makes Aluminium MMC (AMMC) the most promising variant for structural, automotive, marine and aerospace applications. This review opens an insight into the current advancement of AMMCs, detailing an overview on diverse matrices and types of reinforcements that were used to produce such composites. This work also explores and classifies the gain and shortcomings of various phase formations during thermal treatment, revealing the possibilities of improving the physical strength and wear resistance with minimal complexity. This work also highlights the growing concern on corrosion performance of advance AMMC with ceramic reinforcements. In spite of the challenges involved in commercialising AMMC, recent trends of industrial utility reveal their potential to meet evolving demands.

The growing requirement for the product having low cost along with excellent quality has moved work towards composite materials in recent years. Composite materials are very important materials nowadays. A composite material is the mixture of two or more materials, which are having distinct phases and characteristics as well as superior to the base material. Metal matrix composites (MMCs) are constantly evolving due to innovative and exciting technologies and are widely used as well as recognized as a potential material for many industrial applications in various industries. MMCs are having excellent properties in comparison with conventional metals and alloys, in MMCs, a new class of composites, aluminum metal matrix composites (AlMMCs) are gaining increasing attention, AlMMCs are very important for a wide array of applications in industries because of excellent mechanical characteristics, low weight and cost. In the production of MMC materials, there are several production methods available as well as AlMMCs also can be manufactured through a variety of techniques. By changing the methods of the fabrication process and by adding the reinforcement material, different characteristic profiles can be obtained although the materials having the same composition and same quantities. The objective of this article provides a brief overview of the liquid fabrication process focused on the stir casting method and also about various factors, which generally affect the fabrication process.

Lightweight aluminium metal matrix composite materials hold potential requisite for modern tribological applications due to its inherent and better wear resistant properties over monolithic metallic materials. This study emphasised on the development of Al based metal matrix composite with SiCp as a reinforcement and magnesium (Mg) as a wetting agent using hybrid stir casting process. The study further analysed the effects of different size variations of silicon carbide particles such as the coarse particle size, fine particle size, intermediate particle size and mixed particle size in the fabrication of the composites on the hardness and wear properties. The pin-on-disc test was also done at room temperature in a dry sliding wear condition. It was observed that the mixed particle size SiCp in composite exhibited superior hardness with the value of 98.2 compared to other particle sizes of SiCp. This is due to the fact that mixed particle size supports a greater fraction of applied load while the fine and intermediate particle sizes sustain the hardening due to dislocation. The multiple particle size reinforced composite exhibits better performance than the single particle size in terms of wear resistance as the wear rate was the lowest with the value of 0.99 X 10-5. It can be concluded that the Mg addition in the composite showed better and tailored properties with a mixed particle size of SiCp of aluminium metal matrix composite.

Purpose – Since, wear is the one of the most commonly encountered industrial problems leading to frequent replacement of components there is a need to develop metal matrix composites (MMCs) for achieving better wear properties. The purpose of this paper is to fabricate aluminum MMCs to improve the dry sliding wear characteristics. An effective multi-response optimization approach called the principal component analysis (PCA) was used to identify the sets of optimal parameters in dry sliding wear process. Design/methodology/approach – The present work investigates the dry sliding wear behavior of graphite reinforced aluminum composites produced by the molten metal mixing method by means of a pin-on-disc type wear set up. Dry sliding wear tests were carried on graphite reinforced MMCs and its matrix alloy sliding against a steel counter face. Different contact stress, reinforcement percentage, sliding distance and sliding velocity were selected as the control variables and the response selected was wear volume loss (WVL) and coefficient of friction (COF) to evaluate the dry sliding performance. An L25 orthogonal array was employed for the experimental design. Optimization of dry sliding performance of the graphite reinforced MMCs was performed using PCA. Findings – Based on the PCA, the optimum level parameters for overall principal component (PC) of WVL and COF have been identified. Moreover, analysis of variance was performed to know the impact of individual factors on overall PC of WVL and COF. The results indicated that the reinforcement percentage was found to be most effective factor among the other control parameters on dry sliding wear followed by sliding distance, sliding velocity and contact stress. Finally the wear surface morphology of the composites has been investigated using scanning electron microscopy. Practical implications – Various manufacturing techniques are available for processing of MMCs. Each technique has its own advantages and disadvantages. In particular, some techniques are significantly expensive compared to others. Generally the manufacturer prefers the low cost technique. Therefore stir casting technique which was used in this paper for manufacturing of Aluminum MMCs is the best alternative for processing of MMCs in the present commercial sectors. Since the most important criteria of a dry sliding wear behavior is to provide lower WVL and COF, this study has intended to prove the application of PCA technique for solving multi objective optimization problem in wear applications like piston rings, piston rods, cylinder heads and brake rotors, etc. Originality/value – Application of multi-response optimization technique for evaluation of tribological characteristics for Aluminum MMCs made up of graphite particulates is a first-of-its-kind approach in literature. Hence PCA method can be successfully used for multi-response optimization of dry sliding wear process.