Aluminium Alloy Metal Matrix Composites Research Articles

Sustainability in Production and Selection of Reinforcement particles in Aluminium Alloy Metal Matrix Composites: A Review

This paper reviews relevant literature in the area of incorporating sustainable materials into the material selection process of metal matrix composites (MMCs) production. Agricultural and industrial waste materials used as reinforcements in MMCs have been reviewed to highlight the need for establishing a lean production process. The reviewed investigations have recorded improvements in both the microstructure, density and mechanical properties such as hardness, strength, tensile, and impact strength of the resulting MMC. The reviewed literature highlights stir casting as the most used method of producing aluminium and magnesium-based matrix composites due to its relatively low cost, simplicity, and efficiency. Based on the results of various studies, it is highly recommended that the use of these sustainable materials as reinforcements in MMCs possess the necessary properties to be used in engineering industrial applications.

Mechanical Properties and Metallurgical Characterization of LM25/ZrO2 Composites Fabricated by Stir Casting Method

Zirconia (ZrO2) dispersed aluminum alloy metal matrix composites produced by stir casting techniques. Using stir casting techniques, aluminium based composites with varying amounts of 3%, 6%, 9%, and 12% of zirconia by weight are fabricated. The prepared samples were subjected to physical, mechanical,tribiology and microstructure investigation. The extraordinary performance of Aluminium MMCs was the low density that obtained after alloying. Hardness and ductility were also increased when increase in Zirconia particle. Ultimate tensile strength, compressive strength and impact toughness were slightly increasing with the addition of zirconia particle. Microstructural characteristics shows that a homogeneous distribution of particles with reinforcement in casted composite. The investigations of the metallurgical characterization were carried using optical, scanning electron microscope, X-ray diffraction and Energy Dispersive Spectrometry (EDS) test to understand the metallurgical properties. Keywords: Metal-matrix composites (MMCs), Hardness testing, Tensile test, Compression test , Scanning electron microscopy (SEM), Energy Dispersive Spectrometry (EDS).

Microstructural and Mechanical Characterization of Al-4032 based Metal Matrix Composites

Abstract This paper presents an alternative material to the aluminum-silicon alloys used in automotive applications with focus on investigation of the morphological and mechanical behavior of the metal matrix composites formed. The silicon carbide reinforced aluminium alloy (Al-4032) metal matrix composites have been produced through the stir casting technique. Four different compositions, i.e. 0, 3, 6 and 9% (by weight) silicon carbide reinforcement with the particle size 37-54μm have been used. Also, 1% magnesium powder (by weight) has been used for better interfacial bond between the matrix and reinforcement. In general, all the mechanical properties, the tensile strength, hardness, and impact strength have been observed to improve with the reinforcement over the base metal. These properties have also been found to improve with increase in the weight percentage of the reinforcement.

Experimental investigations on mechanical and microstructural properties of Al2O3/SiC reinforced hybrid metal matrix composite

Aluminium alloy metal matrix composites (MMCs) have obtained wide spread acceptance in automotive and aerospace applications because of its high strength, low density and good structural rigidity. This work studies the mechanical and microstructural properties of hybrid metal matrix composite reinforced with Al2O3/SiC prepared by using powder metallurgy technique. Hardness and compressive strength of aluminum matrix composite increased with increase in wt% of SiC. The characterization results showed the improvement in mechanical properties with addition of hybrid reinforcement.

Residual stress and yield strength evolution with annealing treatments in an age-hardenable aluminum alloy matrix composite

We investigated the possibility of minimizing tensile matrix residual stresses in age hardenable aluminum alloy metal matrix composites without detrimentally affect their mechanical properties (such as yield strength). Specifically, we performed thermal treatments at different temperatures and times in an age-hardenable aluminum matrix composite 2014Al-15vol%Al2O3. Using X-ray synchrotron radiation diffraction and mechanical tests, we show that below a certain treatment temperature (250 °C) it is possible to identify an appropriate thermal treatment capable of relaxing residual stress in this composite while even increasing its yield strength, with respect to the as processed conditions.

Cracking evolution behaviors of lightweight materials based on in situ synchrotron X-ray tomography: A review

Damage accumulation and failure behaviors are crucial concerns during the design and service of a critical component, leading researchers and engineers to thoroughly identifying the crack evolution. Third-generation synchrotron radiation X-ray computed microtomography can be used to detect the inner damage evolution of a large-density material or component. This paper provides a brief review of studying the crack initiation and propagation inside lightweight materials with advanced synchrotron three-dimensional (3D) X-ray imaging, such as aluminum materials. Various damage modes under both static and dynamic loading are elucidated for pure aluminum, aluminum alloy matrix, aluminum alloy metal matrix composite, and aluminum alloy welded joint. For aluminum alloy matrix, metallurgical defects (porosity, void, inclusion, precipitate, etc.) or artificial defects (notch, scratch, pit, etc.) strongly affect the crack initiation and propagation. For aluminum alloy metal matrix composites, the fracture occurs either from the particle debonding or voids at the particle/matrix interface, and the void evolution is closely related with fatigued cycles. For the hybrid laser welded aluminum alloy, fatigue cracks usually initiate from gas pores located at the surface or sub-surface and gradually propagate to a quarter ellipse or a typical semi-ellipse profile.

Sliding Tribological Behavior of Al–Fe–V–Si–Graphite Solid-Lubricating Composites at Elevated Temperatures

Aluminum alloy metal matrix composites (Al-MMCs) have been considered as promising materials for aerospace and automotive industries due to their excellent balance of physical, mechanical, and tribological properties. In the present work, the Al–Fe–V–Si alloy matrix composites with 0–20 wt. % copper-coated graphite were fabricated by hot-pressed sintering. The dry sliding tests were carried out at various temperatures ranging from room temperature (RT) to 350 °C. The microstructure, phase, hardness, and worn surface of the sintered composites were examined in detail. The effect of copper-coated graphite amount on the properties of the composite was also investigated. The results show that the Al–Fe–V–Si–graphite composites mainly consist of α-Al, Al8Fe2Si intermetallic, and graphite phases. The addition of Cu-coated graphite can decrease the friction coefficient and wear rate from RT to 350 °C. The Al–Fe–V–Si–graphite composite containing 10 wt. % copper-coated graphite exhibits better wear properties than other composites. The favorable lubricating properties were attributed to the tribolayer with graphite lubricating film formed on the worn surface.

Experimental Evaluation of the Chill Casting Method for the Fabrication of LM-25 Aluminum Alloy-Borosilicate Glass (p) Composites

The paper investigates the novelty of application of end chills in fabricating Aluminum alloy metal matrix composites. An effort has also been made to evaluate the effect of chill material on the soundness of the castings obtained. The required composites were prepared using LM-25 Aluminum alloy as matrix material in which different weight percent of Borosilicate glass particles were added ranging from 3 wt.% to 12 wt.%. The variation in weight percent was brought about in steps of 3%. The fabrication of the composites was carried out in sand molds by incorporating two metallic (copper and Steel) and two non-metallic (Graphite and Silicon carbide) end chills. The specimens for strength and hardness tests were prepared as per ASTM standards and the specimens were drawn from near chill-end as well as from farther away from chill end. The microstructure of the specimens reveal a refined grain structure proving the sound quality of the castings. The result analysis also leads to the conclusion that metallic chills are more beneficial as compared to non-metallic chills for obtaining a good quality composites. Copper chill with a high volumetric heat capacity proved to be the best chill material amongst the others.

Manufacturing of AA2124 Aluminum Alloy Metal Matrix Composites Reinforced by Silicon Carbide Processed by Powder Metallurgy Techniques of High Energy Ball Milling and Hot Extrusion

Aluminum alloy metal matrix composites are a class of materials object of large and intensive research during the last years. In this study an AA2124 aluminum alloy were processed by means of mechanical alloying added by 10, 20 and 20 percent of silicon carbide (SiC) in vibratory SPEX type mill during 60 and 120 minutes. After this the composites powders obtained were characterized by means of Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectroscopy (EDS) to determine the powders morphology. In order to consolidate the AA2124 aluminum alloy composites reinforced by silicon carbide (SiC) composites, the powders processed by high energy ball milling technique were hot extruded and the billets were characterized by SEM to determine the microstructure and the distribution of the reinforced ceramic phase of silicon carbide throughout the aluminum matrix and at last the microhardiness Vickers technique were used to evaluate the mechanical properties.

Experimental Investigation of Optimum level of Reinforcementswithin 6061Al Alloy for betterTribological and Mechanical Properties

Present study aims to fabricate the aluminum alloy metal matrix composite (AAMMCs) by reinforcing aluminum alloy with SiC, Al2O3 and graphite particles for piston ring application. Multiple reinforcements with considerable density difference made the stir casting process most suitable for manufacturing the AAMMCs. The proportion of reinforcements was varied to obtain best composition from the point of view of mechanical and tribological characteristics. Taguchi method was used to determine the number of compositions to be manufactured and ANOVA led us to understand the effect of various reinforcements on the different characteristics of the composite. This finally led to determine the best possible composition of the composite for piston ring. The experiments revealed that the AAMMCs had better properties than the parent aluminium alloy. Mechanical characterization of AAMMCs revealed that tensile strength is improved due to SiC and Al2O3 while graphite has adverse effect on tensile strength and hardness. Tribological characterization of AAMMCs on tribometer revealed that all three reinforcements lead to the improvement in wear resistance but graphite is the only one which has reducing effect on coefficient of friction. SiC improves wear resistance, co-efficient of friction, hardness & strength by 32%, 55%, 30% & 21% respectively. Graphite improves wear resistance by 35% whereas it reduces coefficient of friction, hardness & strength by 33%, 50% & 65% respectively. Al2O3 has the similar effect as that of the SiC but contributes less than that of SiCThe experiments proved that the composition with 4% Al2O3, 7% SiC, 4% graphite is the best amongst the compositions tested as it results in maximum strength and hardness and minimum wear and coefficient of friction.

High Strain Rate Response of A356/Al2O3 Aluminum Alloy MMCs Using Ls-Dyna

Aluminum alloy Metal Matrix Composites (MMCs) have evoked a keen interest in recent times for potential applications in aerospace, defense, marine and automotive industries owing to their superior strength to weight ratio and high temperature resistance despite the higher manufacturing costs. The ability to withstand dynamic loading is an important design criteria for many structures in above applications. The Split Hopkinson Pressure Bar (SHPB) also referred to as Kolsky bar is a commonly used setup for high strain rate test in strain rate range from 102 to 104 s-1. The high strain rate data is required for safety and structural integrity assessment of structures subjected to dynamic loading. As high strain rate data is not easily available in open literature need was felt for setting up such high strain rate testing. Four distinctly different A356/Al2O3 Aluminum alloy MMCs reinforced with 0, 4, 8 and 12% fiber volume fraction of aluminum oxide (Al2O3) particles were prepared using stir casting process. These four different MMCs were numerically characterised with SHPB test setup using Ls-Dyna software. The compressive stress-strain behavior was obtained at different strain rates ranging from 100 to 1200 s-1. The high strain rate results of compressive SHPB for all specimens were obtained in the form of stress-strain graphs, which strongly indicates that the high strain rate affects on the dynamic mechanical behaviour of MMC materials. These results are helpful to select the MMCs for structural applications where materials go under dynamic loading.

Optimization of Wear Behaviour of AA8011-Gr Composite using Taguchi Technique

Composite is a combination of two or more dissimilar materials having a distinct interface between them such that the properties of the resulting material are superior to the individual constituents. Aluminum and its alloys have received major attention as matrix material for Metal Matrix Composites because they have excellent properties such as light weight, high strength to weight ratio, good thermal properties and high wear resistance. The present work aims to investigate 3-body abrasive wear behaviour of graphite (Gr) reinforced Aluminum alloy (AA-8011) metal matrix composite. The composite was prepared by two-step stir casting route. Three-body abrasive wear test was used to explore wear behaviour. The mass of each specimen was measured before and after wear test. Taguchi Technique was used as statistical tool to determine optimum combination of control parameters. L9 orthogonal array was employed and experimental design was based on control factors, Gr. wt.%, time, load and response factor was wear rate to evaluate 3-body abrasive wear performance. Empirical relation was developed for wear rate in terms of control variables by multiple regression analysis. Lastly, Analysis of Variance (ANOVA) was used to assess the influence of individual factors on wear rate. Results were analyzed using the software called MINITAB V.17.1.0. It was observed that time and reinforcement wt.% were the significant factors affecting response variable. Also higher values of reinforcement wt% and time lead to higher wear resistance.

Manufacturing and Characterization of AA1100 Aluminum Alloy Metal Matrix Composites Reinforced by Silicon Carbide and Alumina Processed by Powder Metallurgy

Powder Metallurgy (PM) Techniques consists in a suitable technique to process composites materials. A specific PM technique of mechanical alloying developed to produce new materials in the solid state is a consolidated route to obtain aluminum alloys metal matrix composites. Aluminum alloys metal matrix composites allies the good properties of aluminum and its alloys but with poor mechanical properties and the reinforcement of ceramics phases which add better mechanical properties to these alloys. The research of this materials processing by PM techniques presented new materials with improved properties. In this work an AA1100 aluminum alloy was reinforced by particulate silicon carbide and alumina types of ceramic phases. The powders were mixed and then processed by mechanical alloying in a SPEX vibratory type mill. Then the powders obtained were compacted and vacuum sintered. The sintered composites were characterized by means of Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectroscopy (EDS) and Vickers hardness (HV) tests to evaluate the mechanical behavior.

Fabrication and Performance of Aluminium Based Metal Matrix Composites with SiO<sub>2</sub> and TiO<sub>2</sub> as Reinforced Particles

Aluminum alloys are used in automobile and aerospace industries because of their low density and good mechanical properties, better wear resistance as compared to conventional metals and their alloys. In these industries there is continues demand to develop light weight, inexpensive and strong material which has led to the development of aluminum alloy metal matrix composites with ceramics as reinforcement particles. In this present work, aluminum based metal matrix composites have been fabricated using SiO2 and TiO2 as reinforcement materials by stir casting process and wear behaviour, hardness and breaking load have been evaluated.

Optimization of Influential Parameters on Mechanical Behaviour of AlMg1 SiCu Hybrid Metal Matrix Composites using Taguchi Integrated Fuzzy Approach

Aluminium alloy materials found to the best alternative with its unique capacity of designing the materials to give required properties. Aluminium alloy Metal Matrix Composites (AMMCs) are gaining wide spread acceptance for automobile, industrial, and aerospace applications because of their low density, high strength and good structural rigidity. In this paper, an attempt is made to examine the effect of influential parameters such as type of reinforcement, size of the reinforcing particle and weight percentage on mechanical properties. Stir casting technique has been employed to prepare the composites. The response parameters were tensile strength, impact strength and density. The design of experiments (DOE) approach using taguchi method was employed to analyze the mechanical behaviour of hybrid composites. Fuzzy approach were used to investigate the optimal combination of influencing parameters on the mechanical behaviour.

Features of the Processing of AA2124 Aluminum Alloy Metal Matrix Composites Reinforced by Silicon Nitride Prepared by Powder Metallurgy Techniques

Powder Metallurgy (PM) Techniques consists in a suitable technique to process composites materials. A specific PM technique of mechanical alloying developed to produce new materials in the solid state is a well known route to obtain aluminum alloys metal matrix composites. Aluminum alloys metal matrix composites allies the good properties of aluminum and its alloys but with poor mechanical properties and the reinforcement of ceramics phases which add better mechanical properties to these alloys. The research of this materials processing by PM techniques presented new materials with improved properties. In this work an AA2124 aluminum alloy was reforced by particulated silicon nitride a kind of ceramic phase. The powders were mixed and then processed by mechanical alloying in a SPEX vibratory type mill. Then the powders obtained were compacted and vacuum sintered. The sintered composites were characterized by means of Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectroscopy (EDS) and Vickers hardness tests to evaluate the mechanical behavior.

Heat treatment and plastic deformation in Al3Ti particle reinforced 7050 aluminium alloy matrix composites

7050 aluminium alloy metal matrix composites reinforced with different weight fractions of Al3Ti particles were fabricated using an in situ synthesis method and subsequent rolling, solution and aging treatment. The effects of Al3Ti particle content and particle size on the microstructures and mechanical properties of the composites were investigated by means of hardness measurements, optical microscopy and electron probe. We concluded that the grain size of the composites was smaller than that of the matrix alloy, and with an increase in the plastic deformation, the dispersion of particles was more uniform and fine. It was also found that the hardness of the composites increases with increasing weight fraction and decreasing particle size. By increasing the plastic deformation, the hardness of both the composites increased first and then decreased with the following deformation. In addition, the heat treatment contributed to the hardness.

Evaluation of mechanical properties of aluminium alloy–alumina–boron carbide metal matrix composites

This paper deals with the fabrication and mechanical investigation of aluminium alloy, alumina (Al2O3) and boron carbide metal matrix composites. Aluminium is the matrix metal having properties like light weight, high strength and ease of machinability. Alumina which has better wear resistance, high strength, hardness and boron carbide which has excellent hardness and fracture toughness are added as reinforcements. Here, the fabrication is done by stir casting which involves mixing the required quantities of additives into stirred molten aluminium. After solidification, the samples are prepared and tested to find the various mechanical properties like tensile, flexural, impact and hardness. The internal structure of the composite is observed using Scanning Electron Microscope (SEM).

An Investigation on the Mechanical Properties of Hybrid Metal Matrix Composites

Aluminium alloy materials found to the best alternative with its unique capacity of designing the materials to give required properties. Aluminium alloy Metal Matrix Composites (MMCs) are gaining wide spread acceptance for automobile, industrial, and aerospace applications because of their low density, high strength and good structural rigidity. In the present work, an attempt is made to prepare and compare the mechanical properties of Al6061-SiC & Al6061-SiC/Graphite hybrid composites. The composites were prepared using stir casting method in which amount of reinforcement is varied from 5-15% in steps of 5wt%. The prepared composites are characterized by microstructural studies and density, and mechanical properties were evaluated as per the standards. The microphotographs of the composites revealed fairly uniform distribution of the particles in composites with clustering at few places. The experimental densities were found to be lower than theoretical densities in all the composites. The dispersed Graphite and SiC in Al6061 alloy contributed in enhancing the tensile strength of the composites. The scanning electron micrographs of the samples indicated uniform distribution of the reinforcement particles in the matrix without any voids.

The Effect of Ball Milling & Reinforcement Percentage on Sintered Samples of Aluminium Alloy Metal Matrix Composites

SiC, Al2O3 and Graphene are the major reinforcement in aluminium-based composites, which have been developing rapidly in recent years. This paper focuses on the effect of ball milling & reinforcement percentage on mechanical properties of aluminium alloy metal matrix composites. The average particle size of matrix metal is 10 microns and reinforcements used are SiC, Al2O3 and Graphene of particle size 10 microns and 10 Nano microns. Sintering temperature of 550 oC and time in the range of 10-15min was used to sinter the compacts. It has been concluded that as the fine particle size resulted in good compact densities at 650Mpa of compaction pressure. The green compact has cracked and failed because of two factors such as reinforcement percentage and rate of heating. Based on the findings, the reinforcement percentage is optimized to wt 10% or less than wt 10%.