Aluminium Alloy Based Metal Matrix Research Articles

Optimization of piston material with aluminium alloy based metal matrix composites

Piston failure is caused by a combination of mechanical and thermal loads is a frequent occurrence that can be expensive to repair or replace. In this paper, analysis is carried out to evaluate and improve the performance of a piston intended for deployment in a four-stroke SI engine with a single cylinder. To determine the most suitable material for the piston, different materials, alloys and aluminium based metal matrix composite are examined. Piston is designed using CAD software and static structural analysis and thermal transient analysis is done using finite element analysis. Based on the analysis, Al 6061–1.5% B4C- 1.5% SiC metal matrix composite material is found to be the most desirable choice among the five materials considered due to lower value of deformation (31% to 76% less in comparison) and mechanical stresses (0.38% to 0.83% less in comparison).

Development and evaluation of mechanical properties of aluminium alloys and boron fiber composite material by powder metallurgy route

In recent year, aluminum alloy based metal matrix composites (MMC) are gaining in the field of aerospace and automotive industries, in order to improve by the advancement of modern technology, led to a rapid development of metal matrix composites. Properties can be tailored in the metal matrix composite as per the requirement for specific applications. In these composites the prime function of the fibers is that of supporting most of the applied load, while the role of the matrix is to bind the fibers together and to transmit and distribute the external loads to the individual filaments. Aluminum has been used matrix material owing of its excellent mechanical properties coupled with good formability. Addition of boron fiber as reinforcement inaluminum systemsimprovesthe mechanical propertiesof composites. In the present investigation Al-boron fiber composite was prepared by powder metallurgy route. Powder metallurgy homogeneously distributes the reinforcement in the matrix with no internal reaction and with less porosity. Boron fiber particles containing different weight fractions (5, 10 and 15 %) and mesh size (50 μm and 125 μm) are used as reinforcement. Though Al-boron fiber possess superior mechanical properties, the high abrasiveness of the boron fiber particles obstaclewiderapplication. The Mechanical Properties of Aluminum Alloy (AL2024) were assessed and the compression test was directedatthe material under tempered condition. Al-boron fiber composite has the widest application in the aerospace industry due to high hardness and light weight material. After the development of material that specimens were tested the under the optical, physical and mechanical properties.

Study on Mechanical, Wear and Thermal Properties of AL2O3/Graphite Reinforced AA2024 Aluminum Alloy Based Metal Matrix Composites

Abstract: Metal matrix composites (MMC) play a vital role to satisfy global needs for low low-cost and high-performance mechanical, and thermal properties and quality materials in the composite industry.Aluminium MMCs are preferred to other conventional materials in the fields of aerospace, automotive and marine applications owing to theirimproved propertieslike high strength-to-weightratio, good wear resistance, etc. In the present work, an attempt has been made to synthesize metalmatrix composite using AA2024 as matrix material reinforced with Al2O3 and Graphite (Gr) particulates using a liquid metallurgy route in particularstir casting technique. 2024 aluminium alloyis reinforced by different weight fractions of Al2O3 and Gr particles up to 5 wt%. The effect of wt% of Al2O3 and Gr on the properties such as density, hardness, tensile strength, wear rate, flexural strength, and coefficient of thermal expansion were evaluated. Scanning electron microscope and X-ray Diffraction (XRD) were used to examine the microstructure of the produced hybrid MMC composite. The addition of Al2O3 and Gr pronounced improved mechanical properties and wear. Results indicated that aluminium ceramic composites can be considered as an alternate material for AA2024, where high strength and wear-resistant components are of major importance,particularly in the aerospace and automotive engineering sectors.

Effect of Friction stir processing parameters on microstructure and microhardness of aluminium based Metal matrix composites

The present article demonstrates the Friction Stir Processing (FSP) of the stir cast Aluminium Alloy based Metal Matrix Composites (MMC). Generally, composites manufactured using the stir casting process tends to have several casting defects along with some agglomeration of reinforcement particles. These defects in stir cast composites can be resolved by implementing FSP. MMC was manufactured using the matrix of aluminium alloy 2014, which was reinforced with different weight percent of Silicon Carbide (SiC) particles (5%, 10% and 15%). FSP was performed by considering two different combinations of rotational speed and transverse speed i.e. (i) 270 rpm and 78 mm/min (First Combination) and (ii) 190 rpm and 50 mm/min (Second Combination). The article discusses the variation in microstructure and microhardness of all the friction stir processed composites and the effects of process parameters were examined. Lastly, the conclusion of the article suggests the best combination of processes parameters for performing FSP of manufactured composites.

Role of Reinforcement Particle Size and Its Dispersion on Room Temperature Dry Sliding Wear of AA7075/TiB2 Composites

Aluminum alloy based metal matrix composites (AMCs) are widely accepted material in the aerospace, automotive, military, and defence applications due to lightweight and high strength. For tribological applications, high-performance wear-resistant materials like AMCs are the candidate materials. In this investigation, AA7075 based composites with different size TiB2 particles were fabricated using in-situ and ultrasound casting techniques (UST). The AMCs were tested using pin-on-disc tribo tester and the effects of different sized TiB2 particles on wear resistance of AA7075/TiB2 composites have been investigated. The wear resistance of AA7075/TiB2 composite fabricated using UST is found to significantly improve when compared to base alloy and also in-situ composite due to refinement in the particle size, reduced the agglomeration, and improved the distribution of TiB2 particles. The test results also revealed the existence of a mixture of mechanically mixed Al–Zn–Fe intermetallic alloy and oxides of these elements.

Reinforcements, production techniques and property analysis of AA7075 matrix composites − a critical review

Aluminium alloy based metal matrix composites are being extensively used in the aerospace, automobile, defense, marine and electronic industries owing to their excellent strength, high resistance to wear, corrosion and better thermal stability. Many investigators have explored different aluminium alloy series composites, like heat treatable AA2024, AA6061 and AA7075 since the properties of these matrix alloys can be easily tailor made to suite specific application due to easy processability and heat treatability. AA7075 alloy matrix is predominantly being used, as it exhibits high ultimate tensile strength, resistance to corrosion and fatigue in the group. In the current review work, attention is focused to present types of reinforcing materials used, benefits of reinforcement hybridization, methods employed for composite production and critical property analysis, with conclusions of experimentation and the suggested prospective applications of AA7075 composites. Due to good castability and moldability variety of processing techniques in solid, semisolid and liquid states are possible. As matrix alloy, low processing temperature, ability to accommodate reinforcements and adoptability to different reinforcing techniques, it is easy to obtain optimal properties as per the application. AA7075 with small addition of copper is paved the path in the field of electronic and military applications due to high thermal and electrical conductance. Even pure metal addition & magnesium with copper facilitate good weldability, plasticity and corrosion resistance. Due to the flexibility in accommodating carbide and oxide compound reinforcements in the matrix, this matrix composite widens versatility limit due to excellent hardness and wear resistance. CNT and graphite reinforcements to this aluminium series matrix are marked as ultra-high precision components in defense field.

Parameters optimization and development of multiple regression models for wire electrical discharge machining of aluminium composites

The demand for lightweight materials are increasing nowadays due to emerging industrial applications. AA 2024 is an aluminium alloy, most commonly employed material for various engineering applications such as aircraft structural and automobile applications. The materials added to increase the desired properties are called as reinforcement materials such as Al2O3 and BN, abrasive and leads to more wear on cutting tool and meagre quality in machining surface. Wire Electrical Discharge Machining (WEDM) is an advanced method of material removal which is conceived from the concept of Spark Erosion Machining process. WEDM is mainly employed for machining of hard materials and also especially used for making complex shapes on any electrically conductive work materials. In this present study, an experimental analysis has been performed on WEDM of aluminium alloy based Metal Matrix Composites (AMMC). Peak current (A) Pulse on time (‘Pon’) (µs), Pulse off time (‘Poff’) (µs) are considered as input process parameters in this present analysis. Material Removal Rate (MRR) and Surface Roughness (SR) are considered as desired performance measures that are need to be optimized. Taguchi’s methodology has been implemented for designing and analyzing the experimental runs. An L27 Orthogonal Array (OA) was employed for conducting the experimental runs. The effect of process parameters on desired outputs such as material removal rate (MRR) and surface roughness were investigated by Taguchi’s analysis and ANOVA analysis. Multiple regression equations have been developed for correlating the relationship between the selected input process variable and output variables. Contour plot analysis also performed for disclosing the combined effect of input variables on performance measures.

Effect of Silicon Carbide in Mechanical Properties of Aluminium Alloy Based Metal Matrix Composites

Metal Matrix Composites are a class of composites with evaluated properties that get another perspective of material structure and are generally utilized in the aviation and automobile industry. These materials have the properties of both the base matrix material as well as the reinforced materials. These metal matrix composites have low residual stress and thermal residual stresses. Due to this concept, the materials posses enhanced adhesive bonding between the matrix and reinforcements. Aluminium alloy with silicon carbide is applicable where hardness and toughness are the requirements. Metal Matrix Composites are designed in order to have the combined properties of both metals and ceramics. The specimens are fabricated for various proportions of the materials. In the fabrication, it begins with Aluminium alloy and Silicon carbide. The specimen is evaluated for diverse mechanical tests, and the experimental result is the pure aluminium undergoes more wear when compared to the reinforced specimen.

Frictional property evaluation of aluminium alloy based metal matrix composites under dry braking condition in pin—on—disc system

Aluminum alloy based metal matrix composites are widely used in aerospace, military and automotive industry. The aluminium grades used in present research work are Aluminium alloy 6061, Aluminium alloy 2024, LM6. In this research, composites with Aluminum alloy as matrix with 6 weight % of nano alumina as reinforcement were fabricated using two processing technique namely, powder metallurgy technique (cold pressing and microwave sintering), and by squeeze casting technique. Thus fabricated samples were used to study the effect of processing technique on mechanical properties and wear aspects of the composite. Scanning electron microscope data and mechanical property characteristics reveals the presence of nano alumina particles and their uniform distribution in case of powder metallurgy processed samples. Mechanical and wear properties achieved on the fabricated samples were compared with the existing aerospace brake pad material. The data related to wear characteristics correlated with the number of landings for the existing brake pad material is considered as the bench mark data and the feasibility of replacing it with the developed composites were studied.

Experimental investigation on stir and squeeze casted aluminum alloy composites reinforced with graphene

In the recent past aluminum alloy based metal matrix composites had played a major role in replacing most of the conventional materials. These composites are preferred due to its superior physical and mechanical properties. This research article is intended to compare the mechanical and microstructural properties of aluminum alloy based metal matrix composites manufactured through stir and squeeze casting processes. Metal matrix composite was fabricated using Aluminum alloy 7050 as the matrix and graphene as the reinforcement material. Composites were fabricated with 0.3, 0.5 and 0.7 weight percentage of graphene reinforcement through stir and squeeze casting processes. Microstructures observed on the samples showed uniform distribution of graphene as well as an excellent interfacial bonding with the aluminum matrix. Due to the addition of small quantity of graphene into aluminum alloy matrix, the mechanical properties were enhanced for the samples fabricated through both the processes. The strengthening mechanism of aluminum matrix with graphene addition is found to be favourable due to effective load transfer mechanism and grain refinement. Favorable results were obtained related to mechanical properties with the graphene content of 0.3 wt% through squeeze cast process, which also resulted in defect free castings.

Mechanical and tribology properties of Al-4.5%Cu-5%TiC metal matrix composites for light-weight structures

Aluminum alloy based metal matrix composites has an important role in the field of automobile, aerospace, military and structural applications due to their enhanced mechanical and tribological properties as compared to base aluminum alloys. To enhance the mechanical and tribological properties suitable reinforcement has to be added to the aluminum alloy to fabricate the composites. Present investigation deals with mechanical and wear properties enhancement of Al-4.5%Cu alloy reinforced with 5%TiC in-situ metal matrix composite (MMC) through friction stir processing (FSP) techniques suitable for automobile and aerospace applications. The fabricated composites (Al-4.5%Cu/5%TiC) were hot rolled to remove defects such as porosity and voids. Experiments were conducted using pin-on-disc apparatus against abrasive paper by varying the applied load, sliding distance. The experimental results revealed that the weight loss and co-efficient of friction increases with increase in applied load and sliding distance. The MMC material, Al-4.5%Cu/5%TiC exhibited enhanced ultimate strength and hardness as compared to Al-4.5%Cu alloy. The contribution of TiC as reinforcement is clearly observed with an increase in hardness of the composite as compared with the matrix material. Scanning electron microscopy (SEM) and XRD analysis was done to study the microstructure of the fabricated materials.

Experimental Investigation of Tribological Behaviour of Aluminium Alloy Based Metal Matrix Composites

Metal Matrix Composites are a class of advanced composites with graded properties that bring a new concept in material design and are widely used in the aerospace and automotive industry. These materials have the properties of both the matrix as well as the reinforcement materials. They are known to have little residual and thermal stress. This concept imparts improved adhesive bonding strength between metals and ceramics. Aluminium alloy with silicon carbide is applicable where hardness and toughness are the requirements. Metal Matrix Composites are designed in order to have the combined properties of both metals and ceramics. The specimens are fabricated for various proportions of the materials. In the fabrication of these materials, begins with Aluminium alloy and Silicon carbide. The specimen is subjected to different mechanical tests, and the experimental result is the pure aluminium undergoes more wear when compared to the reinforced specimen.

Mechanical and Tribological Properties of AA7075 Based MMC Processed through Ultrasound Assisted Casting Technique

Aluminum alloy based metal matrix composites play an important role in the field of automobile, aerospace, military and structural applications due to their improved mechanical and tribological properties as compared to base aluminum alloys. To enhance the mechanical and tribological properties, suitable reinforcement particles are added in to the aluminum alloy to form a composite. In this investigation an attempt has been made to develop a composite (AA7075/5%TiB2) suitable for automobile and aerospace applications with improved mechanical and tribological properties through in-situ and ultrasound assisted in-situ processing techniques. Further, these composites have been subjected to hot forging. Hardness tests were carried out in order to study the mechanical properties of the composite. The test results showed that the addition of TiB2 particles improves the hardness. Micrographs reveal the uniform distribution of TiB2 particles surrounded along the grain boundaries and this leads to improved mechanical properties. Wear tests have been carried out using pin-on-disc tribo tester. Wear test results showed that the addition of TiB2 particles enhance the wear resistance of composite and co-efficient of friction decreases significantly by processing techniques such as in-situ and ultrasound. Superior grain refinement leading to improved mechanical and tribological properties of the composite has also been observed after hot forging.

Encapsulation and microwave hybrid processing of Al 6061–Graphene–SiC composites

ABSTRACTThe demand for new aluminum alloy–based metal matrix composites with combinations of novel reinforcements, processed through innovative methods are very much needed for critical engineering applications. With this perspective, the current research work is aimed at the development of Al 6061 composites reinforced with two-dimensional Graphene nanoflake-encapsulated SiC. Ultrasonic liquid processing method is used to disperse the Graphene flake and the mixture is ball milled by adding SiC to achieve the encapsulation. Subsequently, the Al 6061 powder is added to the milled mixture and consolidated through uniaxial vacuum hot press followed by microwave hybrid sintering. Scanning electron microscope (SEM) analysis, X-ray diffraction analysis, hardness, density, and microstructure analysis were carried out on developed composites. Raman analysis was carried out to analyze the distortion on Graphene physical structure during various processing stages. Further, effects on novel combination of material with combined processing approach on flexural and tribological behavior have been analyzed.

Fabrication and characterisation of Al2O3/aluminium alloy 6061 composites fabricated by Stir casting

Aluminium alloy based metal matrix composites (AMMC) are widely used for sliding wear applications because of their excellent wear resistant properties. AMMC are fabricated using various methods like liquid state fabrication, solid state fabrication methods, etc. It was found that stir casting is an economical method to fabricate AMMC. In the present work, aluminium alloy 6061 reinforced with various percentages of Al2O3 particles (5, 10, 15 and 20 wt%) were prepared. At first the stir casting set up was prepared as per the requirement. The objectives of this research work are the fabrication and characterisation of AA 6061/ Al2O3 AMMC which was fabricated using stir casting process. The microstructures of AMMC were studied using scanning electron microscopy. Al2O3 particles were observed to refine the grains and were distributed homogeneously in the aluminium matrix. Al2O3 particles clusters were also seen in a few places.Al2O3 particles were properly bonded to the aluminium matrix. The reinforcement of Al203 particles improved the micro hardness and ultimate tensile strength of AMMC.

Processing methods and property evaluation of Al2O3 and SiC reinforced metal matrix composites based on aluminium 2xxx alloys

Abstract

A COMPARATIVE INVESTIGATION ON PHYSICAL AND MECHANICAL PROPERTIES OF MMC REINFORCED WITH WASTE MATERIALS

Abstract— Aluminium alloy based metal matrix composites (MMC) are produced with agro waste Rice Husk Ash (RHA) and industrial waste Fly Ash as reinforcement. By the continuous stir casting method the MMCs were fabricated in a bottom pouring furnace at 7000C. A rectangular metal mould was used to prepare the casting having dimension 300x50x20 mm3. The effect of adding the different reinforcement were realized through various mechanical behaviour tests. Based upon the standards in the mechanical workshop samples were prepared for measuring mechanical properties such as Impact strength, Compression strength, Tensile strength, Brinell hardness and Density test of both the MMCs. The Fly Ash and Rice Husk distributions in the MMCs were confirmed through the examinations conducted of the microstructure on image analyzer and scanning electron micrographs. Results thus found revealed that there is a great effect of reinforcing Flyash and Rice Husk in aluminium alloy matrix composites. Fly ash gave more enhanced mechanical properties as compared to Rice Husk. Thus selection of waste material from industry based and agro based for reinforcement was found one of the most important criteria for fabricating aluminium matrix composites.

Impacts of Nano Particles on Fatigue Strength of Aluminum Based Metal Matrix Composites for Aerospace

Nanotechnology is spreading massively in the different demanding fields of engineering and medicines like defence, aerospace, automobiles, electronics, information and communication technology. This present research article deals with study of dual Nano sized particles reinforcement impacts on the fatigue life of AA7075-T651 grade aluminum alloy based Metal Matrix Nanocomposites (MMNCs) which is produced by emerging stir casting process. Nano particles are effectively enhancing the mechanical properties in the metal matrix composite than micron level particles because of its bonding nature. So for, the Nanoparticles were reinforced at three different volume fractions in parent metal such as Nano SiC 5%, 10% and 15% with constant Nano Al2O3 of 5% to produce the Nanocomposites. Fatigue behavior has become progressively more established as technology and it has developed a larger amount of equipment such as aircrafts, compressors, pumps, gas pipelines, oil tanks, pistons, turbines and many more subject to repeated loading and vibration. Therefore, in this investigation, the fatigue life of the produced MMNCs were investigated by advanced rotating beam fatigue testing machine to understand the impacts of reinforced Nano particles and the integrity of the MMNCs were examined by Optical Microcopy (OM) and Scanning Electron Microscopy (SEM).

Mechanical and Morphological Studies of Al6061-Gr-SiC Hybrid Metal Matrix Composites

Abstract. In recent years, Aluminium alloy based metal matrix composites (MMC) are gaining wide spread acceptance in several aerospace and automobile applications. These composites possess excellent wear resistance in addition to other superior mechanical properties such as strength, modulus and hardness when compared with conventional alloys. The hybrid composites are new generation of composites containing more than one type, shape or sizes of reinforcements giving superior combined properties of reinforcements and the matrix. In the present work, Al6061 has been used as matrix material and the reinforcing materials selected were SiC and Graphite particulates of 10 to 30µm size. Composites Al6061-Gr (2- 8 wt. %), Al6061-SiC (2 -10wt. %) and Hybrid composites with Al6061 matrix alloy containing 3wt% graphite and varying composition of 2-10wt% SiCp were prepared by stir casting technique. The cast matrix alloy and its composites have been subjected to solutionizing treatment at a temperature of 530 ± 20C for 6 hours, followed by ageing at a temperature of 175 ± 20C for 6 hours. The mechanical properties of as cast and T6 heat treated composites have been evaluated as per ASTM standards and compared. Addition of Graphite particulates into the Al6061 matrix improved the strength and ductility of the composites. Significant improvement in tensile strength and hardness was noticed as the wt. % of SiCp increases in Al6061-SiC composites. Addition of Graphite into Al6061-SiC further improved the strength and ductility of hybrid composites. The heat treatment process had the profound effect in improving the mechanical properties of the studied composites. The microstructural studies revealed the uniform distribution of SiC and Gr particles in the matrix system.

Synthesis and Characterization of A356-Sicp Composite Produced through Vacuum Hot Pressing

The aim of this research is to analyze the effect of SiC particle addition and heat treatment on the microstructure and mechanical and thermal properties of A356 aluminum alloy–based metal matrix composite. Aluminum alloy powder in the size range 25–50 µm and SiC particles of 1 µm average size in 0, 5, 10, 15, and 20 volume percentages were used as raw materials. Powders were blended in a ball mill and then sintered in vacuum hot press. The hot pressed composites were heat treated using T6 heat treatment. Microstructure analysis was carried out to assess the distribution of the SiC particles in the Al matrix. Hardness, tensile strength, compressive strength, and coefficient of thermal expansion (CTE) have been measured both on base alloy and composite materials, before and after the heat treatment. The result showed that addition of SiC particles improved the hardness, compressive strength, and decreased the CTE on both heat treated and as hot pressed samples. However, the tensile strength increased with increase in SiC particles in the range 5 to 15% and then decreased for composite with 20% of SiC particles.