Al2O3 Metal Matrix Composites Research Articles

A Review on Distribution of Reinforcement and tensile Strength of Aluminum Lithium Alloy based Nano Metal Matrix Composites Fabricated by STIR Casting

Aluminum Alloy (AA) parts are employed in lightweight engineering fields and have poor mechanical, wear, and corrosion resistance. Aluminum Matrix Composites (AMCs) are materials created by incorporating hard reinforcing particles into an aluminum matrix alloy. The new material has improved characteristics, including higher specific stiffness and strength, as well as higher corrosion resistance, elastic modulus, wear resistance, and low weight. Metal Matrix Composites (MMCs) are composite materials in which metal serves as the matrix and hard particles or ceramics serve as reinforcement. MMCs are used to improve the functionality of a wide range of technical materials. It could be used in many different fields, including aerospace, automotive, space travel, and medicine. In this paper, the reviewer investigates the distribution of reinforcement and Tensile Strength (TS) of Aluminum Lithium (Al-Li) Alloy/Nano Al2O3 MMC fabricated by stir casting. Finally, the authors provide a comparative analysis of prior reviewed research papers. After comparative analysis, TiB2/2195 composite has higher Tensile Strength (115.4%) than the other composite such as AA7010-TiB2 (260%), Al2O3 + SiC (72%), A356/SiC (21.87%), and Al-SiC (37%).

Microstructure mechanical behavior of Cu-Sn alloy reinforced with Al2o3 and Graphene metal matrix composite

In the present study, an effort has been made to examine the Microstructure and Wear characteristics of composites manufactured from Cu + 10 wt% Sn alloy as matrix and reinforced with Graphene Oxide (GO) and Alumina. Cu + 10 wt% Sn alloy hybrid composites is prepared reinforced with alumina (10 vol%) and altering weight percentage of Graphene oxide (0.25 wt%, 0.5 wt% and 1 wt%) by spark plasma sintering technique. Wear characteristics of developed composites is studied using Pin on Disc Wear Testing machine. Utilizing optical microscopy the microstructural investigation is conducted. The results revealed that (Cu + 10 wt% Sn alloy-10 vol% Al2O3-0.25 wt% GO) and (Cu + 10 wt% Sn alloy-10 vol% Al2O3 − 0.5% wt%) of hybrid nanocomposite showed an increase of 25 % in the hardness, a reduction of 25% in the wear rate for Cu + 10 wt% Sn alloy-10 vol% Al2O3-0.25 wt% GO and Cu + 10 wt% Sn alloy-10 vol% Al2O3 − 0.5% wt% GO of hybrid nanocomposite, and an increase trend wear rate is observed with increase in applied load and disc speed in dry pin on disc wear testing. The result also revealed the uniform reinforcement distribution in microstructure and more than 95 % densification of all composites with spark plasma sintering process.

Microstructural Evolution, Tensile Failure, Fatigue Behavior and Wear Properties of Al2O3 Reinforced Al2014 Alloy T6 Heat Treated Metal Composites.

The paper focused on an experimental study on the microstructural, mechanical, and wear characteristics of 15 wt.% alumina (Al2O3) particulates with an average particle size of 20 µm, reinforced in Al2014 alloy matrix composite as-cast and heat-treated samples. The metal matrix composite (MMC)samples were produced via a novel two-stage stir-casting technique. The fabricated composite samples were subjected to evaluate hardness, tensile strength, fatigue behavior and wear properties for both as cast and T6 heat-treated test samples. The Al2014 alloy and Al2014-15 wt.% Al2O3 MMCs were in solution for 1 h at a temperature of 525 °C, quenched instantly in cold water, and then artificially aged for 10 h at a temperature of 175 °C. SEM and X-ray diffraction analyses were used to investigate the microstructure and dispersion of the reinforced Al2O3 particles in the composite and the base alloy Al2014. The obtained results indicated that the hardness, tensile and fatigue strength and wear resistance increased when an amount of Al2O3 particles was added, compared to the as-cast Al2014 alloy and it was observed that after subjecting the same composite samples to heat treatment, there was further enhancement in the mechanical and wear properties in the Al2014 matrix alloy and Al2014-15 wt.% Al2O3 composite samples.

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

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

Mechanical behavior and characterization of Al7075 reinforced with Al2O3 and TiC Hybrid metal matrix composite

The fabrication and analysis of Aluminium 7075 Metal Matrix composite is designed to set up the use of a substitute metal for aerospace applications. Aviation and car businesses are enthusiastic on presenting mixture metal grid composites in their segments because of their excellent mechanical and wear properties, prompting decrease in the weight underlying segments and energy prerequisite for driving. This research paper includes investigation of the mechanical properties of the Al7075 reinforced with 6 wt% of Aluminium Oxide and various weight percent (wt%) of Titanium Carbide (TiC) in micron level particles manufactured by stir casting technique. The examination of mechanical properties like hardness, tensile strength, impact strength (Charpy) was investigated. The microstructure concentrated by scanning electron microscope instruments is done to notice the kind of fortified particles conveyance in composite. Results from wear test showed that the wear rates of the pin on disc Al7075 alloy and composites increasing with applied load. The mechanical properties of the created composites are looked at and reasonable suggestions will be proposed. We additionally confronted imperatives to acquire the parts consistent with the ASTM testing norms.

Parametric test for identifying significant factors which affect weight loss for Al2O3 and SiC metal matrix composite

Metal matrix composites have gained wide importance and have found various application. It is highly imperative in understanding the behavior of material properties under various conditions. This would lead to obtaining significant insight into the working behavior of the composite. This particular work focuses on gathering insights through statistical analysis especially using parametric test. Four sets of material composition for an Aluminum copper alloy were analyzed for no reinforcement to various combination of reinforcement of Silicon Carbide for a fixed percentage of Alumina. The statistical study involved conducting a parametric test to identify whether there is a significant difference among the various levels for factors such as time of test, speed, and load play a role in affecting the weight loss. The parametric test involved are two sample t test, paired t test.

Mechanical Properties of AA 5754 Hybrid Metal Matrix Composite Fabricated through Rheo-Squeeze Casting

Hybrid metal matrix composites (MMCs) were prepared with AA 5754 as matrix and B4C (fixed with 1 wt.% and average particle size as 25 μm) and Al2O3 reinforcements (varied from 0.5 to 2 wt. % with the interval of 0.5 and average particle size as 50 nm) using Rheo-squeeze casting process. Microstructure images were taken to observe the uniform distribution of reinforcement particles on the matrix alloy. The tensile strength for AA 5754 with 1 wt.% B4C and 2 wt.% Al2O3 hybrid composite showed higher value compared to base alloy and other composites. The wt. % of Al2O3 in the composite is increased to 2 %, the tensile strength and compressive strength were also increased due to combined Rheo-squeeze casting. AA 5754 reinforced with 1 wt.% B4C and 1.5 wt.% Al2O3 MMC indicated the Impact strength value of 30 Joules which is higher than AA 5754 matrix alloy and other compositions.

Characterization, corrosion and failure strength analysis of Al7075 influenced with B4C and Nano-Al2O3 composite using online acoustic emission

This paper aims to establish the mechanical, corrosion and failure analysis using online acoustic emission of Al7075 alloy, Al7075-B4C composite and Al7075- B4C-Al2O3 hybrid composite with different Boron Carbide (B4C) content of 5, 10, 15 & 20% and Nano Aluminium Oxide (Al2O3) content of 2% on a weight basis with the high energy stir casting method. The casted samples have been characterized by x-ray Diffraction (XRD), Thermo gravimetric analysis (TGA/DSC), Energy Dispersive Spectrum (EDS), and Scanning Electron Microscope (SEM). In case of hybrid composite, the hardness and the tensile strength decrease when the content of Al2O3 increases. However, in the present research, the addition of B4C with nano Al2O3 particles in certain proportions has increased the hardness and tensile strength. In addition, the tensile fractographs of the specimens were analysed using SEM. Acoustic Emission (AE) method was used for monitoring the acoustic energy that are released at the time of deformation process and early crack detection. The influence of the volume fraction of the B4C particulates on the microstructural and corrosion characteristics of Al7075- B4C with nano Al2O3 metal matrix composites (MMCs) was also studied. It has been observed from the literature that the direct strengthening of composites occurs due to the presence of hard ceramic phase, while the indirect strengthening arises from the thermal mismatch between the matrix alloy and reinforcing phase during solidification. Based on the database for material properties, the application area of HAMCs has been proposed in the present review. The effects of nanomaterial dispersion in the metal matrix and the formation of interfacial precipitates on these properties are also addressed. Particular attention is paid to the fundamentals and the structure–property relationships of such novel Nano composites.

Processing and Property Evaluation of Nano Al2O3 Reinforced Copper- 5% Tin Composites for Bearing Applications

Nano technology has fascinated the attention of numerous material scientists and design engineers. The nano scaled particulates incorporation exhibit many attractive and special properties. The inclusion of nano particulates into the copper matrix might augments the hardness, ultimate tensile strength and yield strength significantly increases, maintaining the ductility. In this paper, the nano Al2O3 reinforced copper - 5%tin- metal matrix composites were manufactured by stir casting technique and reinforcement is varied from 0wt. % to 9wt. % in ventures of 3wt. %. The nano composites are characterized in terms of their mechanical and wear properties. Results revealed that, the distribution of nano Al2O3 particulates is fairly uniform in copper - 5%tin metal matrix. As the level of reinforcement increases, hardness, yield strength, ultimate tensile strength, and wear resistance of the copper - 5%tin – nano Al2O3 metal matrix composites increases. The developed nano metal matrix composites may be an alternative material for bearing applications

EXPERIMENTAL INVESTIGATION ON ELECTRICAL PROPERTIES AND WEAR RATE OF ALUMINUM MATRIX NANOCOMPOSITE (AMNC) OF AA7100/Al2O3

In this study AA7100/6wt% Al2O3 metal matrix composite (AMMS) wassuccessfully manufactured using stir casting route. The influence of 6wt% Al2O3content on microstructure, electrical properties and wearresistance were investigated . The microstructure of composite revealed thathomogeneity of Al2O3 particles in the matrix and also the reinforcement ofgrains compared to matrix grains. The homogeneity and reinforcement can beattributed to enhance the electrical and wear properties and this perhaps coulddue to efficiency of stirring process during the casting. The 6wt% Al2O3content shifted the conductivity and permittivity from reducing in matrix toincreasing in the composite when the frequency increased. The wear resistancewas improved due to addition of 6wt% Al2O3 compared to matrix.

Mechanical and tribological characterization nitrided Al-7075/Al2O3 metal matrix composites

This research is mainly intended to evaluate the effect of nitriding on the wear behaviour of Al2O3 reinforced aluminium-7075 metal matrix composite materials. The composites were prepared by using powder metallurgy process. The amount of Al2O3 in these composites was varied from 3% to 7% (by weight) in steps of 2%. Homogeneously mixed powder by using double cone mixture was compacted using hydraulic press with 60KN of load. The compaction load was optimized to get a equal density as base specimens,then the compacted specimens were sintered at 5400 C which is 80% of melting temperature aluminium base alloy. The sintered materials were nitrided with a temperature of 520°C for 72hrs. Two different set of specimens, namely, nitrided composites and non-nitrided composites specimens were tested for their wear resistance and hardness properties. Pin-on-disc equipment was used for wear testing and microhardness testing machine was used for hardness testing. Elemental X-Ray Diffraction technique (XRD) was used to ensure the diffusion of nitrogen to the surface of composites. After all the standard tests it was observed that the nitrided composites have shown better wear resistance than the non-nitrided composites

Mechanical characterization of PM aluminum composites by small punch test

In this work Small Punch Test (SPT) was applied to study the mechanical behavior of ultrafine-grained Al- Al2O3metal matrix composites (MMCs) fabricated in situ via powder metallurgy route (HITEMAL®). Such MMCs show attractive mechanical properties, enhanced creep performance and increased thermal stability at elevated temperatures, not normally associated with service of conventional Al alloys, even after prolonged high temperature exposure. MMCs fabricated from two powders of different particle size (d50 = 8.9 and 1.2μm) were evaluated in the present work. SPT was performed at room temperature using disc-shaped specimens of 10 mm in diameter. The effect of the different disc thickness (0.4, 0.5 and 0.6 mm) on the load vs. displacement function was evaluated. The displacements monitored from top and bottom sites of the specimen varied during the course of the test. The discs deformed throughout the test by two plastic stages, typical for ductile materials. The relation between load-displacement and stress–strain tensile curves for both composites was analyzed. A drastic change of mechanical behavior between the green compact of cold pressed material and the hot forged material was detected. New methods of determination of a characteristic load PY, which represents a transition from elastic to plastic bending regime were presented and discussed. A relationship between PY and corresponding yield stress was studied for each composite material by a calculation of their respective correlation parameters. Keywords: Small punch test, powder metallurgy, yield strength, aluminum, composite, correlation parameter.

Selective laser melting of stainless steel and alumina composite: Experimental and simulation studies on processing parameters, microstructure and mechanical properties

Metal matrix composites (MMC) find their uses as high performance materials. The selective laser melting (SLM) of a 316L stainless steel and Al2O3 MMC is presented in this paper. Agglomerate Al2O3 particles had shown to be an adequate powder choice with uniform dispersions in the resultant prints. Relative density, phase, microstructure and mechanical properties of all 1-, 2-, 3-wt% doped products were carefully analyzed. Finite element modeling model was developed to study the associated multi-physics phenomena with high efficiency for process parameter optimization. It is found that the change in SLM temperature profile with Al2O3 addition is mainly due to the change in optical properties rather than thermal. Hence, both simulation and experimentation revealed that higher laser energy input is needed for optimized melting. In addition, cellular dendrites were found to coarsen with increasing Al2O3 addition due to the decreased cooling rate. With hard particle strengthening effects, all samples showed improved hardness with 3-wt% up to 298HV and 1-wt% samples showing much improved yielding and tensile stresses of 579 and 662MPa from 316L. Corresponding microlattice built this way demonstrated a 30 and 23% increase in specific strength and energy absorption from that of 316L too.

In situ analysis of damage evolution in an Al/$$\hbox {Al}_{2}\hbox {O}_{3}$$Al2O3 MMC under tensile load by synchrotron X-ray refraction imaging

The in situ analysis of the damage evolution in a metal matrix composite (MMC) using synchrotron X-ray refraction radiography (SXRR) is presented. The investigated material is an Al alloy (6061)/10 vol $$\%$$ $$\hbox {Al}_{2}\hbox {O}_{3}$$ MMC after T6 heat treatment. In an interrupted tensile test the gauge section of dog bone-shaped specimens is imaged in different states of tensile loading. On the basis of the SXRR images, the relative change of the specific surface (proportional to the amount of damage) in the course of tensile loading was analyzed. It could be shown that the damage can be detected by SXRR already at a stage of tensile loading, in which no observation of damage is possible with radiographic absorption-based imaging methods. Moreover, the quantitative analysis of the SXRR images reveals that the amount of damage increases homogeneously by an average of 25% with respect to the initial state. To corroborate the experimental findings, the damage distribution was imaged in 3D after the final tensile loading by synchrotron X-ray refraction computed tomography (SXRCT) and absorption-based synchrotron X-ray computed tomography (SXCT). It could be evidenced that defects and damages cause pronounced indications in the SXRCT images.

Optimization of Machining Parameters for CNC Turning of Al/Al2O3 MMC Using RSM Approach

This paper discusses the influence of cutting variables such as feed, cutting speed and depth of cut at work-tool interface zone temperature and surface finish while machining aluminium alloy LM6 reinforced with Al2O3 metal matrix composites. Response surface methodology with central composite rotatable design matrix was employed to optimise and analyse the cutting variables. Second order regression models were developed for predicting the output responses and the adequacy of the developed model was tested using analysis of variance (ANOVA). ANOVA results revealed that the feed and depth of cut were the major influencing parameters for the work-tool interface temperature and cutting speed and feed were prominent influential parameters in surface roughness. The optimal parameters for multiple responses were arrived for the specified range of input parameters using overall desirability index.

Lightweight Al-stabilized MgB2 conductor made by the IMD process

Light single-core MgB2 wire stabilized by a unique Al–Al2O3 metal matrix composite (MMC) was fabricated by the internal magnesium diffusion (IMD) process. Mg/B/Ta/Al–Al2O3 composite was cold-deformed into a wire with a cross section of ∼1 mm, and finally heat-treated at temperatures of 635 °C–645 °C for times of 8–60 min. Critical temperatures and critical currents were evaluated by transport and magnetic measurements. Thermal stability and AC loss were characterized by the quench power from I–V curves and by the hysteresis loss measured by a calibration-free method. The results obtained clearly confirmed that the Al–Al2O3 MMC mechanically supports the Mg/B/Ta wire core well during cold-working operations and subsequent heat treatment to form MgB2, while at the same time it retains its advantageous mechanical properties, and it can be utilized as a material for the outer sheath of MgB2 superconductors. Critical temperatures and critical current densities of MgB2/Ta/Al–Al2O3 are comparable with the values for other superconductors with MgB2 core fabricated by the IMD process using different sheath materials. The composition presented here shows promising potential for future lightweight and thermally stable superconducting MgB2 wires with high engineering current density.

Properties of near- and sub-micrometre Al matrix composites strengthened with nano-scale in-situ Al2O3 aimed for low temperature applications

Mechanical and electrical properties of in-situ Al–Al2O3 metal matrix composites (MMCs) fabricated by powder metallurgy approach using different aluminium powders of particle size 0.8–21µm and purity 99.8–99.996% were examined. Hot working powder consolidation by vacuum hot pressing at 270°C and direct extrusion at 425°C and reduction ratio of 7:1 were applied. Subsequently, extruded composite rods with the diameter of 7.5mm were cold worked by groove rolling and rotary swaging to the wires with the diameter of 1.1mm. Detailed microstructural characterization of composite materials was carried out. Stress-strain characteristics of composite wires were measured at 77 and 300K. In addition, resistivity of all wires were measured by four-probe method between 25 and 300K and eddy current losses at frequency 72Hz and temperatures between 18 and 77K. Obtained results clearly showed that properly designed Al–Al2O3 MMC materials can be utilized at low temperatures e.g., for the thermal stabilization of superconducting wires.

Microstructure and Tensile Properties of Mg (AM60)/Al2O3 Metal Matrix Composites with Varying Volume Fractions of Fiber Reinforcement

Magnesium alloy AM60 matrix-based composite reinforced with 7, 9, 11, 22, and 35 vol.% of Al2O3 fibers was squeeze cast. The microstructure and mechanical properties were investigated in comparison with the matrix alloy AM60. The results of tensile testing indicated that the addition of Al2O3 fibers to magnesium alloy AM60 led to a significant improvement in mechanical properties. As the fiber volume fraction increased, the strengths and moduli of the composites were enhanced considerably. However, the notable increase in strengths was at sacrifice in elongation. Microstructural analyses via scanning electron microscopy (SEM) revealed that the grain size decreased with increasing volume fractions of reinforcement. The restriction of grain growth by the limited inter-fiber spacing could be the primary mechanism for a reduction in the grain size of the matrix alloy. The SEM fractography evidently reveals that the debonding of fibers from the matrix alloy and the fiber cracking were two primary mechanisms for the tensile failure of the composites.

Closed Die Deformation Behavior of Cylindrical Iron–Alumina Metal Matrix Composites During Cold Sinter Forging

The present paper aims to study the closed die deformation behavior of cylindrical Fe–Al2O3 metal matrix composites (MMCs). Closed die was manufactured by machining the high carbon steel block followed by oil quenching and then finishing. Samples sintered at a temperature of 1100 °C for 1 h were characterized with X-ray diffraction and scanning electron microscopy, which showed the formation of Fe, Al2O3 and nano size FeAl2O4 phases respectively. Density and hardness of the composite samples were determined after sintering. Closed die deformation studies of the prepared composite samples were carried under three different interfacial frictional conditions i.e. dry, solid lubricating and liquid lubricating. Hardness, density and metallographic characterizations were also done for the deformed samples. On comparing the micrographs of the samples before and after deformation it was revealed that in deformed specimens recrystallization has taken place due to the difference in the energy between the strained iron matrix and unstrained alumina reinforcement during closed die forging process. Experimental density of the samples was also verified with the theoretical density using the standard equations. It is expected that the results of the present investigations will be helpful in developing quality MMC components for wide industrial applications.

Mechanical and Wear Properties of Al–Al2O3 Metal Matrix Composites Fabricated by the Combined Effect of Stir and Squeeze Casting Method

The effects of nano particles on double shear strength and tribological properties of A356 alloy reinforced with Al2O3 nano particles of size 30 nm were investigated. The percentage inclusions of Al2O3 were varied from 0.5 to 1.5 wt%. The particles were added with stirring at 400 rpm and squeeze casting at 750 °C and pressure of 600 MPa in a squeeze casting machine. Comparison of the performance of as cast samples of A356/Al2O3 nano composite was conducted. The tribological properties of the samples were also investigated by pin-on-disk tests at 10, 30 and 50 N load, sliding speed 0.534 m/s and sliding distance 1100 m in dry condition. SEM images of microstructure analysis of the composite, Al2O3 (0.5 and 1 %) particles were well dispersed in the A356 alloy matrix. Partial agglomeration was observed in metal matrix composite with higher (1.5 %) Al2O3 particle contents. The nano dispersed composites containing 0.5 and 1 wt% of Al2O3 nano particles exhibited the highest double shear strength, lesser wear loss and coefficient of friction.