Papers by Keyword: Metal Matrix Composite

Abstract: The trade-off between strength and toughness remains a major challenge in structural materials engineering, especially for titanium-based materials. This study explores the potential of titanium-based laminates for lightweight armor, aimed at improving anti-ballistic properties through the use of layered structures. Titanium alloy Ti-6Al-4V (Ti64) was combined with metal matrix composites (MMCs) reinforced with TiC or TiB particles (up to 40 vol%) using two powder metallurgy (PM) techniques. The first approach used press-and-sinter blended elemental powder metallurgy (BEPM) to create the laminates in a single step, while the second involved post-processing via hot isostatic pressing (HIP) to enhance material properties. Both fabrication methods produced laminates that significantly outperformed commercial alternatives in ballistic testing against 7.62 mm armor-piercing bullets. The use of HIP post-BEPM enhances material properties by reducing porosity and increasing hardness, highlighting the complementary nature of these technologies in producing efficient and cost-effective armor materials.

Abstract: Electrochemical Machining (ECM) is a modern metal working process that make it possible to machine products that are challenging or even impossible to create using traditional machining methods. This study aims to explore how surface roughness and machining rate in ECM are influenced by magnetic field on the metal matrix composite with different machining process input. Neodymium magnets were employed to generate the magnetic field during experiments. The workpiece material used in this experiment is aluminum 6061 alloy, Al-B4C, Al-SiC and the tool material is copper. The input parameter used in this experiment was varying such as electrolyte concentration, voltage, gap, and type of material. Minitab software was used to analyze the results and orthogonal arrays are used in the Taguchi design of the experiment. The results showed that in all experiments, the magneto hydrodynamic effect both reduces surface roughness and increases the machining rate. Furthermore, the Al6061 alloy exhibited the smoothest surface finish and the highest machining rate.

Abstract: This study investigates the thermal distribution in high-stregth AA2124/SiC/25p-T4 metal matrix composite during friction stir welding (FSW), a process that allows welding of these materials that are difficult or impossible to be welded by conventional welding methods. To understand the process mechanisms, a transient, 3D thermo-mechanical finite element mode (FEM) was developed. The model calculates temperature distribution during FSW welding by considering boundary conditions such as rotational speed, welding speed, tool pressure, tool diameter and material properties, accounting for conduction and convection heat transfer. The numerical results are validated against experimental data, demonstrating the model’s effectiveness in predicting the impact of varying parameters and aiding in the selection of optimal welding conditions before costly physical trials.

Abstract: Metal matrix composites (MMCs) have received considerable attention due to their low density with good elastic modulus and high strength to weight ratio. Discontinuous reinforced Ti matrix composites have been found as a promising material for applications in various fields, such as aerospace, automotive, biomedical and advanced military applications, because of their low cost, improved performance and ease of fabrication. Among the discontinuous ceramic reinforcements, TiC is identified as a very suitable reinforcement for the Ti system because of its excellent properties and high compatibility with Ti matrices. In this study, investigations have been conducted on the influence of volumetric percentage of TiC (10%) on microstructural development of TiC reinforced titanium beta matrix composite prepared by the blended elemental method from hydrided powders using ex situ processing route. Samples were produced by mixing of elemental hydrided powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering (900°C- 1500°C), in high vacuum. Sintered samples were characterized for phase composition, microstructure, microhardness and mechanical properties by X-ray diffraction, scanning electron microscopy, Vickers indentation, respectively. Density was measured by Archimedes method. The experiment results revealed that TiC content has significant influence on the microstructure and improving the hardness values of Ti-35Nb-TiC composites. A homogeneous distribution of TiC particles was observed, with a reduced presence of agglomerates and macroporosities. There was an increase of 28.5 % in the hardness of the composites with the addiction of TiC, which indicates the possibility of using components manufactured using this technique, for example, in aircraft landing gears that are subject to high mechanical stress and orthopedic implants.

Abstract: In the aerospace industry, titanium and its alloys have garnered significant attention for their low density, rendering them highly desirable materials. Nonetheless, their wear resistance has posed challenges, prompting extensive research into titanium-based composite materials. This study investigates the tribological performance of various titanium-based metal specimens reinforced with distinct ceramic and intermetallic materials. Specifically, specimens were fabricated to include a 20% volume fraction of pre-alloyed TiAl intermetallics, renowned for their reduced density, while others incorporated 30% boron carbide (B₄C). All specimens were meticulously prepared using Inductive Hot Pressing under optimized conditions. The primary objective is to discern the most effective option in terms of wear resistance. Comprehensive analyses, encompassing mass loss measurements, track width evaluations, wear assessments, and friction coefficient analyses, were conducted to achieve this goal.

Abstract: This study aims to investigate the wear behavior of AA7075 alloy with the reinforcement of Silicon carbide (SiC) and Boron carbide (B4C) particles. Process parameters are crucial for component quality improvement, particularly in metal matrix composites (MMCs), a unique class of materials used in a variety of technical applications, such as but not limited to automobiles, marine, and aeronautics.These are frequently utilized in challenging applications due to their significantly better strength to weight ratios, stiffness, and then standard materials. However, it has numerous disadvantages, including high weight ratios, high deformation and stresses, poor fatigue life cycle, early wear and friction, and so on. Up till now, numerous reinforcements have been employed to address these crucial problems. Due to its superior properties, aluminum matrix composites (AMCs) have been used in many different applications. This work attempts to examine the wear behavior of AA7075 alloy reinforced with silicon (SiC) and boron (B4C) particles utilizing the stir casting process AA 7075-(SiC)-(B4C) composites were produced by employing AA 7075 as the matrix material with silicon carbide (SiC) and boron carbide (B4C) particles as reinforcement in various percentages of weight (5%, 10%, and 15%). Parameters of the composites, including wear behavior, coefficient of friction, frictional force, and pin temperature were assessed through graphical representation.

Abstract: In the current research, titanium carbide (TiC) is used to reinforce the aluminium alloy (AA 6063) in stir-cast hybrid composites at concentrations of 5, 10, and 15 weight percent together with 3 weight percent of graphite. The application of this developed composite is mainly used for automobile suspension parts. The portrayal of characters was performed, and the mechanical properties of the fabricated samples were investigated. Composites with different TiC weight percentages have their mechanical properties, including hardness, tensile strength, compressive strength, and flexural strength, measured and assessed. The results are shows that AA 6063 alloy with 3 wt. percentage of graphite with an increasing weight percentage of TiC composites are better in the mechanical property. The hardness of the AA 6063 alloy composites is greater than that of the base matrix alloy. The tensile strength of Al 6063 alloy composites has been reported to grow with increasing TiC particle content and to be significantly higher than the strength of the matrix alloy. Also, the SEM microstructure images clearly shows that 15 weight percentage of TiC with 3 weight percentage of Graphite shows the maximum distribution in the matrix.

Abstract: Mechanical properties of graphene nanoplatelets (GNPs) reinforced aluminum matrix composite fabricated by the semi-solid stir casting method were investigated. Aluminum alloy A356 is selected based on being widely used in automotive and aircraft industries. Recently, graphene has attracted wide attention from a scientific committee due to its outstanding properties. GNPs are an ideal reinforcement for nanocomposites' productions due to their excellent mechanical properties for strength enhancement. In this study, the effect of different weight fraction of GNPs content (0,0.3,0.5,1.0,and 1.5 wt.%) reinforced with A356 aluminum alloy was analysed. A 45-degree carbide impeller performed the stirring process of 500 rpm for 5 minutes. The samples were then characterised by microscopic examination, Vickers hardness, and tensile test Morphology of the fracture surface of the composite were observed using scanning electron microscopy..The microstructure revealed a homogenous distribution of nanoparticles in the matrix alloy. The composite exhibits improved mechanical properties, maximum tensile strength and hardness of 236MPa and 83 HV are obtained respectively. The composite has shown significant enhancement in the tensile and hardness which is 20% times higher than unreinforced A356 alloy. The hardness increased as the weight fractions of GNP in the A356 matrix has increased. However, when the content of GNPs used above 1.0 wt%, its tensile strength is reduced. Meanwhile, the fracture sample is ductile with a fine dimple structure. These findings may contribute to the process field of semi-solid stir casting, particularly on the GNPs addition to aluminium alloy as their primary material.

Abstract: Metal matrix composites (MMCs) are now one of the most significant groups of modern engineering materials as a result of the increased attention they have received in recent years. MMCs have recently been manufactured using a variety of technical specifications and techniques, with properties such as the ability to withstand thermal stability at the lowest possible cost, reduced weight and density, increased strength and toughness, and improved wear resistance. It is crucial to homogenize the distribution of the reinforcing phase during composite processing in order to generate particulate or fibrous solid microstructures, depending on the form of the reinforcing phase of the composite. This implies that new procedures must be employed to enhance the mechanical and microstructural properties of metal products. One of the answers to the above challenges is friction stir processing (FSP). FSP improves the surface quality, ductility, formability, strength, hardness, and fatigue life of metal alloys without altering the properties of metals in bulk. This study aims to review MMCs suitable for FSP-designed marine structures and identify knowledge gaps. According to the literature, MMCs are advanced materials capable of exhibiting microstructure, increased hardness, strength, excellent damping, wear, and reduced thermal expansion, making them suitable for a wide range of applications. Although FSP is recognized as a new secondary processing approach to enhance the microstructure and properties of MMCs, few studies have reported the production of MMCs suitable for marine applications. Therefore, this opens a large gap that needs to be filled and requires further investigation of MMCs development.

Abstract: This paper discusses Copper Metal Matrix Composites. It is obvious that copper matrix composites have been heavily relied upon by many industries because of their high wear resistance, corrosion resistance, excellent electrocatalytic properties, and high strength. The excellent electrical conductivity of copper-based materials also enables these materials to function as lubricants and anti-frictional materials. These materials were widely used in transportation, electrical contact transmission, and aerospace. Copper-based metal matrix composites have wide application due to their excellent mechanical, electrical, and thermal characteristics. Copper based metal matrix composites are also corrosion resistant and have a high strength. A contemporary study evaluated the effects of different parameters on powder metallurgy fabricated copper matrix metal composites. The focus was on understanding the applications and mechanical properties of copper-based composite materials.