Ceramic Reinforced Aluminum Matrix Composites Research Articles

Investigating coherent and semi-coherent interfacial structures and energetics in [formula omitted] interfaces: Theoretical insights into aluminum matrix composites bonding

Understanding the intricate interfacial structures and energetics between ceramics and aluminum is crucial for elucidating the mechanical properties of aluminum matrix composites (AMCs). However, previous theoretical simulations primarily focused on coherent interfaces, neglecting lattice constant variations on heterogeneous interfaces, which has led to discrepancies with experimentally observed semi-coherent interfaces. Here, using recently synthesized Al/Al3BC AMCs as a case study to systematically construct six semi-coherent interfacial models containing 383 to 588 atoms. These models are used to investigate the Al(11¯1)/Al3BC(0001) and Al(3¯11¯)/Al3BC(0001) structures and their associated energetics. Additionally, we examine 39 coherent interfaces for comparison. Work of adhesion and interfacial energy results reveal that the stable termination for semi-coherent interfaces is Al(B), which contrasts with AlC termination observed in coherent interfaces. Both Al(11¯1)/Al3BC(0001) and Al(3¯11¯)/Al3BC(0001) semi-coherent interfaces demonstrate higher stability but lower bonding strength compared to coherent interfaces. Bonding strength and stability of Al(B)-terminated semi-coherent interface in Al(3¯11¯)/Al3BC(0001) are lower than those in Al(11¯1)/Al3BC(0001). Electronic structure analysis indicates that AlC-terminated coherent interface exhibits greater charge transfer and stronger covalent metal bonds, while the Al(B)-terminated semi-coherent interface shows less charge transfer and more pronounced metallic bond characteristics. These computational insights provide valuable theoretical understanding of interfacial bonding mechanisms inherent in ceramic-reinforced AMCs.

Aluminium matrix composites reinforced with high entropy alloys: A comprehensive review on interfacial reactions, mechanical, corrosion, and tribological characteristics

Aluminium matrix composites (AMCs) reinforced with high entropy alloy particulates (HEAp) represent an innovative category of metal-matrix composites with considerable potential for fulfilling the stringent demands of emerging technological applications. Their appeal lies in the advantageous combination of toughness, strength, ductility, and enhanced workability, addressing acknowledged limitations associated with ceramic-reinforced AMCs. The heightened performance of these composites is attributed to improved wettability between the aluminium matrix and HEAp reinforcement, alongside the intrinsic ductility and hardness of HEAp. This review explores the suitability of high entropy alloys as substitutes for ceramic materials in reinforcing aluminium matrix composites. The mechanical, corrosion, thermal and wear properties of AMCs reinforced with HEAp are thoroughly examined, encompassing fabrication characteristics and interfacial reactions. The incorporation of HEAp is found to notably enhance the strength-ductility ratio of AMCs. Remarkably, HEAp bring about significant improvements in the wear and corrosion resistance of AMCs. The report accentuates the performance benefits and certain challenges associated with the application of HEAp reinforcement in AMCs. Ultimately, this review proposes potential avenues for future research in this domain, outlining directions for further exploration and development.

Microstructure formation and mechanical performance of micro-nanoscale ceramic reinforced aluminum matrix composites manufactured by laser powder bed fusion

The constituent ratio merged into as-fabricated composites can directly influence the content of in-situ formed reinforcing phases, which is closely related to the mechanical performance of these composites. In this work, aluminum matrix composites reinforced with 10, 15, and 20 wt% (ZrC+TiC) ceramic fractions have been manufactured by laser powder bed fusion (LPBF) additive manufacturing. The effect of hybrid ceramic reinforcement content on laser absorption behavior, fabrication and fraction of micro-nanoscale reinforcing phases, mechanical performance of the as-fabricated aluminum matrix composites is studied. In the laser processing, TiC reacts with ZrC to synthesize interfacial layer on the unmolten ceramic particals and precipitate nano-particles. With the hybrid ceramic content raising from 10 to 20 wt%, the laser absorption behavior is enhanced, and the nano-particle fraction increases. The micro/nano hardness of the composites with 20 wt% ceramic content, reaches 120 HV0.2 and 1.33 GPa, respectively. An elastic modulus of ∼94.4 GPa and tensile strength of ∼280 MPa are obtained for the 15 wt% (ZrC+TiC)/Al composites, much higher than those of the unreinforced Al matrix. This is attributed to the combination of formation of nano-precipitates and coherent bonding at the reinforcement/matrix interfaces in these composites.

The effect of Argon Shield Gas and Cold Air for Friction Stir Welding of Ceramic-reinforced Aluminium Matrix Composite and Aluminium Alloy

A dissimilar joint between friction stir welded ceramic-reinforced C35 aluminium matrix composite and AA7075-T6 aluminium alloy has some difficulties. For fusion welding of aluminium, a shielding gas always has to be used to achieve the required welding joint quality, but in the case of Friction Stir Welding (FSW) no shielding gas or filler material is required for welding aluminium alloys. To achieve a good welding joint between super strength aluminium alloys and ceramic-reinforced aluminium matrix composites some sort of support is needed. In this study, the effect of blowing argon gas and cold air (0 °C) was investigated with regards to the quality of the welding. For the experiment a cylindrical pin tool, a different feed and a constant rotation speed were utilized along with a marble table to avoid harmful heat conduction. For evaluations, hardness and tensile tests examinations were carried out to classify the mechanical properties of the joint. Experimental results showed that the blowing of gas and cold air having a positive effect on the welded joint quality and also for the weld face. Additionally, the optimal welding traveling speed and the temperature of the air blown was determined.

Numerical analysis of heat transfer in electric motor casing made of ceramic reinforced aluminium matrix composites

Sustainable and renewable energy is the need of the hour. Scientists and Engineers around the world are pushing for electric vehicles and electrically run machines to save the environment from pollution and global warming, to create a sustainable planet for us humans to live. The aim of the present research work is to understand the heat transfer characteristics of an electric motor casing made of Aluminium Metal Matrix Composites (AMMCs) so as to implement such casings on a larger scale. As aluminium composites are light in weight, this would improve the performance and efficiency of the electric motor in the long run, and when thought about at the global level considering the new upcoming age of electric vehicles, the slightest of improvements could produce a major impact in the upcoming years. The CAD model of the casing is designed using Solidworks software. This model is used to conduct Finite Element Steady State Heat Transfer analysis in Ansys software to study the heat transfer characteristics. Five AMMCs are chosen for analysis. A comparative study is made based on the weight of the casing and the heat transfer characteristics for each material. Al/Graphite composite is found to produce promising results in the heat transfer domain.

Mechanical properties of Al-Cu/B4C and Al-Mg/B4C metal matrix composites

Abstract To be able to successfully produce ceramic-reinforced aluminum matrix composites by using the powder metallurgy method, the wetting of ceramic reinforcements should be increased. In addition, the negative effects of the oxide layer of the aluminum matrix on sinterability should be minimized. In order to break the oxide layer, the deoxidation property of Mg can be used. Furthermore, by creating a liquid phase, both wettability and sinterability can be improved. In this study, the effects of Mg and Cu alloy elements and sintering phase on the wettability, sinterability, and mechanical properties of Al/B4C composites were investigated. For this purpose, various amounts (5, 10, 20, and 30 wt.-%) of B4C reinforced Al5Cu and Al5Mg matrix composites were produced by the powder metallurgy method. After pressing under 400 MPa pressure, composite samples were sintered for 4 hours. The sintering was carried out in two different groups as solid phase sintering at 560 °C and liquid phase sintering at 610 °C. Despite the deoxidation effect of Mg in Al5Mg matrix composites, higher mechanical properties were determined in Al5Cu composites which were sintered in liquid phase because wettability increased. The highest mechanical properties were obtained in the 20 wt.-% B4C reinforced Al5Cu sample sintered in liquid phase.

Effect of Trace Addition of Ceramic on Microstructure Development and Mechanical Properties of Selective Laser Melted AlSi10Mg Alloy

Selective laser melting (SLM) is an emerging additive manufacturing technology for fabricating aluminum alloys and aluminum matrix composites. Nevertheless, it remains unclear how to improve the properties of laser manufactured aluminum alloy by adding ceramic reinforcing particles. Here the effect of trace addition of TiB2 ceramic (1% weight fraction) on microstructural and mechanical properties of SLM-produced AlSi10Mg composite parts was investigated. The densification level increased with increasing laser power and decreasing scan speed. A near fully dense composite part (99.37%) with smooth surface morphology and elevated inter-layer bonding was successfully obtained. A decrease of lattice plane distance was identified by X-ray diffraction with the laser scan speed decreased, which implied that the crystal lattices were distorted due to the dissolution of Si and TiB2 particles. A homogeneous composite microstructure with the distribution of surface-smoothened TiB2 particles was present, and a small amount of Si particles precipitated at the interface between reinforcing particles and matrix. In contrast to the AlSi10Mg alloy, the composites showed a stabilized microhardness distribution. A higher ultimate tensile strength of 380.0 MPa, yield strength of 250.4 MPa and elongation of 3.43% were obtained even with a trace amount of ceramic addition. The improvement of tensile properties can be attributed to multiple mechanisms including solid solution strengthening, load-bearing strengthening and dispersion strengthening. This research provides a theoretical basis for ceramic reinforced aluminum matrix composites by additive manufacturing.

Development of aluminium-based composites reinforced with steel and graphite particles: structural, mechanical and wear characterization

Apparent limitations in toughness and ductility of ceramic reinforced aluminium matrix composites have prompted considerations of metallic reinforcements. In the present study, the structural characteristics, mechanical and wear behaviour of stir cast Al-Mg-Si alloy-based composites reinforced with different weight percent of steel-, steel-graphite hybrid mix-, and SiC-particles were investigated. The results show that the hardness of the composites increased approximately by 11% with increase in steel particles from 4 to 8wt.%. For the same range of steel concentration, the ultimate tensile strength also increased with increase in steel wt.%. These strength values were all higher than that of 8wt.% reinforced SiC by a margin of 3.2–24%. The specific strength and fracture toughness equally followed the same trend with respect to steel concentration with strain to fracture, the exception where slight decrease (less than 4%) is observed. For these properties, the values were superior to the SiC reinforced composite and ascribed to improved grain refinement and interface bonding, and the inherent ductility of the steel particles. For the 8wt.% hybrid reinforced composite compositions containing steel and graphite, all the mechanical properties decreased slightly with increase in graphite content and trailed the composite reinforced with 8wt.% steel. However, the wear rates were lowest for the hybrid reinforcement mix of steel and graphite, followed by those containing only steel; while that reinforced with SiC had the highest wear susceptibility. Nonetheless, abrasive wear was the dominant wear mechanism observed in all the composites.

Corrosion behavior of SiC foam ceramic reinforced Al–23Si composites in NaCl solution

SiC foam ceramic reinforced aluminum matrix composites (SFCAMCs) were prepared by squeeze casting aluminum alloy (Al–23Si) into the SiC foam ceramic with different pore sizes, and the corrosion behavior of the SFCAMCs was studied in NaCl solutions. Static immersion corrosion tests were conducted at 20 °C, 50 °C and 80 °C, respectively. Corrosion morphology and products were analyzed by scanning electron microscope, energy dispersive system and X-ray diffraction. It was found that the corrosion rate of SFCAMCs increases as the temperature rising, and the bigger pore size of SiC foam ceramic reinforcement, the better corrosion resistance of SFCAMCs.

Tool wear in turning ceramic reinforced aluminum matrix composites—A review

Cutting tool wear during turning of ceramic reinforced aluminum matrix composites was reviewed. Though tools of different materials, such as tungsten carbide, coated tungsten carbide, ceramics, cubic boron nitride, polycrystalline cubic boron nitride, chemical vapor deposition diamond coated tungsten carbide, and polycrystalline diamond were used for turning the aluminum matrix composites, better performance of polycrystalline diamond tools was observed in terms of tool life. The results obtained by many researchers indicated that dominant tool wear mechanism was abrasion, and tool life was mainly affected by flank wear during turning of these composites. The flank wear increased on increasing particulate size or weight fraction of reinforcement. Flank wear of the cutting tool also increased with increasing cutting speed, feed, and depth of cut; however, cutting speed was the most significant parameter affecting flank wear, followed by feed. Influence of depth of cut on flank wear was limited or insignificant.

Properties of ceramic-reinforced aluminium matrix composites - a review

Abstract A review of various properties of ceramic-reinforced aluminium matrix composites is presented in this paper. The properties discussed include microstructural, optical, physical and mechanical behaviour of ceramic-reinforced aluminium matrix composites and effects of reinforcement fraction, particle size, heat treatment and extrusion process on these properties. The results obtained by many researchers indicated the uniform distribution of reinforced particles with localized agglomeration at some places, when the metal matrix composite was processed through stir casting method. The density, hardness, compressive strength and toughness increased with increasing reinforcement fraction; however, these properties may reduce in the presence of porosity in the composite material. The particle size of reinforcements affected the hardness adversely. Tensile strength and flexural strength were observed to be increased up to a certain reinforcement fraction in the composites, beyond which these were reduced. The mechanical properties of the composite materials were improved by either thermal treatment or extrusion process. Initiation and growth of fine microcracks leading to macroscopic failure, ductile failure of the aluminium matrix, combination of particle fracture and particle pull-out, overload failure under tension and brittle fracture were the failure mode and mechanisms, as observed by previous researchers, during fractography analysis of tensile specimens of ceramic-reinforced aluminium matrix composites.

Fabrication and heat treatment of ceramic-reinforced aluminium matrix composites - a review

Abstract Ceramic-reinforced aluminium matrix composites have attracted considerable attention in engineering applications as a result of their relatively low costs and characteristic isotropic properties. Reinforcement materials include carbides, nitrides and oxides. In an effort to achieve optimality in structure and properties of ceramic-reinforced metal matrix composites (MMCs), various fabrication and heat treatment techniques have evolved over the last 20 years. In this paper, the status of the research and development in fabrication and heat treatment techniques of ceramic-reinforced aluminium matrix composites is reviewed, with a major focus on material systems in terms of chemical compositions, weight or volume fraction, particle size of reinforcement, fabrication methods and heat treatment procedures. Various optical measurement techniques used by the researchers are highlighted. Also, limitations and needs of the technique in composite fabrication are presented in the literature. The full potential of various methods for fabricating ceramic-reinforced aluminium matrix composites is yet to be explored.

Mechanical Properties and Wear Behaviour of Al2O3/SiCp Reinforced Aluminium-Based MMCs Produced by the Stir Casting Technique

In this study, initially Al2O3/SiC powder mix was prepared by reacting of aqueous solution of aluminium sulphate, ammonium sulphate and water containing SiC particles at 1200°C. 10 wt% of this hybrid ceramic powder with different sized SiC particles was added to a liquid Al matrix alloy during mechanical stirring between solidus and liqudus under inert conditions. Then hybrid Metal Matrix Composites (MMCs) was produced. The effect of reinforced particle size on tensile strength, bending strength, hardness resistance and wear resistance properties of hybrid reinforced MMCs were investigated. The mechanical test results revealed that bending, tensile strength and hardness resistance of the composites increased with decrease in ductility, with decrease size of the reinforcing SiC particulates in the aluminium alloy metal matrix. The wear behaviour of the hybrid ceramic reinforced aluminium matrix composites was investigated using pin-on-disc test at room temperature under dry conditions. Wear tests showed that the wear resistance of MMCs increased with increasing reinforced Al2O3/SiC particle size. Comparing the fine particle size MMCs with the coarse particle size MMCs were easily pulled out whole from the matrix. Microstructural examination showed that as well as coarse SiC particle reinforcement, a fine alumina particle reinforcement phase was observed within the aluminium matrix (A332).

Surface modification of Al–Al 2O 3 composites by laser treatment

Heat treatment of ceramic-reinforced aluminium matrix composites (AMCs) using a high-power diode laser (HPDL) was investigated. AMCs were treated by irradiation with laser beams of different power and scanning speeds. This resulted in significant changes in the overall appearance and microstructure of the composite material. Contact gauge profilometry and combined SEM–EDXS and XRD analyses were performed to investigate the relationship between changes in the morphology and microstructure to the amount of laser energy delivered. Vickers microhardness and tribological tests were performed to identify changes in the local mechanical properties of the composite material. Laser treatment often improves the properties of AMCs, although setting of the operational parameters is crucial. In fact, small deviations in power and/or scan speed can severely damage the material, leading to deterioration of the microstructure and overall mechanical behaviour.

Modelling of the prediction of tensile and density properties in particle reinforced metal matrix composites by using neural networks

In this study, density and tensile strengths properties of Al 2O 3/SiC particle reinforced metal matrix composites (MMCs), which is produced by using stirr casting process, are predicted by designing a back-propagation neural network that uses a gradient descent learning algorithm. Firstly, to prepare a training set some results has been experimentally obtained. In the experiments, Al 2O 3/SiC powder mix has been prepared by reacting of aqueous solution of aluminium sulphate, ammonium sulphate and water containing SiC particles at 1200 °C. Ten percent vol. of this dual ceramic powder with different SiC particle size ranges was added into liquid matrix alloy (A332) during mechanical stirring between solidus and liqudus under inert condition [Altinkok N, Demir A, Ozsert İ. Composite Part A 2003;34:577–8. [1]]. Density and tensile strengths of dual ceramic reinforced aluminium matrix composites have been investigated at room temperature. In the neural networks training module, it were used different SiC (μm) particle size ranges as input and density and tensile strengths in produced MMCs. Then, neural network is trained using the data obtained in experimental process. In this paper, density and tensile strengths in produced MMCs have been estimated for different SiC (μm) particles size range by using neural network efficiently instead of time consuming experimental processes.

Study of SiC/Al nanocomposites under high pressure

Ceramic reinforced Aluminium matrix composites which possess high specific strength and stiffness will receive wide applications in the near future. The discontinuous-type of reinforcement, for example SiC, has been especially appealing due to its relative availability and low cost production. In this paper, pressure method has been used to make nanometer-sized SiC particle, which obtained from laser-induced vapor-phase reactions and average particle diameter is about 25 nm, in Al matrix to form SiC/Al nanocomposites. Effects of the particle size and agglomerate state of SiC on the configuration of the grain boundary, microstructural development, as well as sinterability of SiC/Al nanocomposites under different pressure and temperature conditions, were studied by TEM, SEM and X-ray diffraction.