Metal Matrix Research Articles

Structure and mechanical properties of consolidated billets from recycled chip wastes of cast metal matrix composites of the Al-Si-SiC system

This study examines the structure and mechanical properties of billets produced via hot pressing from ball-milled chips of Al-Si-SiC metal matrix composites. The chips, derived from cast composites, were subjected to high-energy ball milling to obtain powder, which was then consolidated by hot pressing at 450 °C. The findings reveal that machining reduces the average size of SiC particles from 41.9 to 12.9 µm, and ball milling further reduces it to 5.9 µm. Powder-pressed billets exhibited a more homogeneous SiC distribution and showed ∼1.9 times higher hardness than the cast material, while chip-pressed billets showed only a ∼13 % increase. Compression tests indicated the highest yield strength of 333 ± 7 MPa in powder-pressed samples, compared to 225 ± 6 MPa in the cast state and 143 ± 26 MPa in chip-pressed samples. However, powder-pressed samples had lower ductility (∼3 %) than cast and chip-pressed samples. The influence of hot pressing temperature (350–500 °C) on the structure and mechanical properties was also explored, showing that higher temperatures improve silicon distribution but slightly reduce hardness and yield strength. Recycled composite materials from chip waste are promising for producing consolidated billets, especially for small-sized components in machinery and instrument engineering.

Influence of heat treatment on metallurgical and mechanical properties of aluminium Al6061 hybrid metal matrix composites

Abstract The current investigation explores the metallurgical and mechanical properties of hybrid metal matrix composites (HMMC) with aluminum 6061 as the base material, reinforced with ceramic of tungsten carbide (WC) nanoparticles, graphite (as a solid lubricant) and redmud (RM). Four different composites with tungsten carbide nanoparticles (1.5 wt.%) and graphite (2 wt.%) with a varying proportions of redmud (0, 1, 3 and 5 wt.%) are fabricated by stir casting. Microscopic analysis reveals grain boundary with segregations, some of which dissolve to form discontinuous grain boundaries after heat treatment. FESEM examination shows the formation of intermetallic, some of which dissolve on heat treatment to form precipitate that are distributed evenly along the grain boundary and also inside grains. EDX mapping further validated the uniform distribution of reinforcements without any agglomeration. The addition of reinforcements and heat treatment (T6) resulted in substantial improvements in hardness, ultimate tensile strength, yield strength, and compressive strength compared to unreinforced Al6061 and untreated HMMC, respectively. Fractographic analysis of tensile tested samples reveals the presence of dimples, tearing edges and small voids, indicating ductile fracture.

Comparative tribological study of the material intended for a lightweight HAMNC brake rotor sliding against NAO brake pad material

Abstract The present work studies the lightweight Hybrid Aluminium Metal Matrix Nanocomposite (HAMNC) for brake rotor application. The novel HAMNC brake rotor material is fabricated by reinforcing 1 wt. % nano Boron carbide (nB4C) and 0.75 wt.% nano Titanium dioxide (nTiO2) employing ultrasonic-squeeze-assisted stir-casting process. The developed HAMNC and a commercial Gray Cast Iron (GCI) brake rotor material was subjected to density, hardness, thermal, corrosion, and tribological studies. The results indicated that the HAMNC brake rotor material is 60% lighter and extremely corrosive resistant compared with GCI material. Also, the dry sliding wear study done using Non Asbestos Organic (NAO) commercial brake pad as the pin material exhibited that the HAMNC brake rotor material possessed a higher wear-resistant behavior compared to GCI.

Characterization of bauxite residue filled sisal/glass fiber reinforced hybrid composites for structural applications

Abstract Composite materials with high compressive, flexural, and shear strength are essential for constructing various structural elements in automotive, aerospace, marine, and construction sectors. The present research aims to create bauxite residue filled sisal/glass fiber reinforced polyester composites. The different weight percentages of sisal fiber (35 %, 30 %, 25 %, and 20 %), red mud (0 %, 5 %, 10 %, and 15 %), glass fiber (5 %), and polyester matrix (60 %) were used to fabricate composites. The combined use of compression molding and hand layup technique was employed in the creation of composite materials due to its frequent utilization in the manufacturing of large-scale components found in various sectors, including automotive, aerospace, marine, and construction. In this work, investigated the physical, compressive, flexural and v notch rail shear strength of the fabricated composites. Results revealed that the composites with 30 % of sisal fiber and 5 % of red mud has the highest compressive, flexural, and v notch rail shear strength of 83.45 MPa, 182.74 MPa, and 10 MPa, respectively. Further, this composite showed high density, less void content, and less thickness swelling than other composites. According to the outcomes, this composite material demonstrates suitability for various structural applications across automotive, aerospace, marine, and construction sectors.

Mechanical properties and damage mechanism of SMAHC laminates

Abstract The combination of smart materials and composite materials to achieve lightweight and intelligent structures has been an important research direction in recent years. In this paper, a three-dimensional woven hybrid shape memory alloy (SMA actuator) is modularly implanted into a composite laminate to prepare a SMA hybrid composite (SMAHC) laminate. The orthogonal test was designed with the three variables of SMA actuator modular implantation position, SMA pre-strain and SMA number. According to the orthogonal test results and finite element results, the influence of the three variables on the stiffness before heating, the stiffness change rate after heating and the strength of SMAHC laminates was studied. According to the test index, the influence of the three variables on the results was further evaluated. The results show that the implantation position has the greatest influence on the mechanical properties of SMAHC laminates, followed by SMA pre-strain, and the number of SMA has the least influence. The location and form of damage of SMAHC laminates are further summarized, and the bending damage mechanism of SMAHC laminates is analyzed.

Recent Research on the Optimization of Interfacial Structure and Interfacial Interaction Mechanisms of Metal Matrix Composites: A Review

Interfaces in metal matrix composites (MMCs) are crucial in determining the mechanical properties and functionality of MMCs. This article reviews recent scientific advances and issues related to MMC interfaces from four different perspectives: interfacial structural design, interfacial defect control, thermodynamics and kinetics of interfacial reactions, and interfacial microstructure properties‐based numerical simulation. The influence of interfacial microstructural features on interfacial strength–toughness trade‐offs and their functionality is given special attention. The interfacial problem is still one of the main challenges to be solved in the composite system, which is mainly reflected in the following aspects: interfacial microstructure–deformation mechanisms in complex systems, precise control of interfacial defects and interfacial reaction products, and the efficient and cost‐effective application of numerical simulation techniques. The integrated computation and intelligent design (artificial intelligence) of composites through multiscale computational simulation with the guidance of “interface design‐property prediction” will be the key area of MMC interface research in the future.

Structure–property relationships and nanofiller‐induced hydro‐anti‐plasticization in polyhydroxyurethane/POSS hybrid composites

AbstractNon‐isocyanate polyhydroxyurethanes/polyhedral oligomeric silsesquioxane (PHU/POSS) hybrid composites are prepared by in situ physical introduction of octa(3‐hydroxy‐3‐ethylbutyldimethylsiloxy) POSS into a linear non‐isocyanate polyhydroxyurethane matrix. The amorphous nature of the matrix is retained in the composites and no POSS crystals are observed. Thermal and mechanical properties are studied along with water‐polymer interactions and are discussed in terms of structure‐properties relationships. POSS has only minimal effect on thermal stability. Composite materials with up to 2 wt% POSS exhibit an increased rubbery modulus. The glass transition temperature of the composite materials increases up to 2 wt% loading and decreases at higher POSS content. Water‐polymer interactions are studied in a broad range of relative humidity (0–0.97). Materials exhibit a relatively high water absorption, which is enhanced by POSS at low concentrations. Moisture sorption isotherms are discussed in terms of the Guggenheim‐Anderson‐de Boer model. The study of molecular mobility of hydrated systems by differential scanning calorimetry reveals a peculiar POSS‐induced antiplasticization in PHU/POSS blends at 10–20 wt% water uptake, possibly due to the formation of POSS‐centered water clusters.

Review of Wear and Mechanical Characteristics of Al-Si Alloy Matrix Composites Reinforced with Natural Minerals

Al-Si alloys are vital in the aerospace and automotive industries due to their high strength-to-weight ratio, excellent ductility, and superior corrosion resistance. These properties, along with good thermal conductivity, low thermal expansion, and enhanced wear resistance due to silicon, make them ideal for lightweight, high-performance components like engine parts exposed to harsh conditions and thermal cycling. In recent years, the development of aluminium metal matrix composites using Al-Si alloys as the base material has gathered significant attention. These composites are engineered by integrating various reinforcing particles into the aluminium matrix, which results in remarkable improvements in the wear resistance, hardness, and overall mechanical performance of the material. The stir casting process, a well-established and cost-effective method, is frequently employed to ensure a uniform distribution of these reinforcing particles within the matrix. This review delves into the influence of different types of reinforcing particles on the properties of Al-Si alloy-based AMCs. The incorporation of these reinforcements has been shown to significantly enhance wear resistance, reduce friction, and improve the overall strength and toughness of the composites, making them ideal candidates for high-performance applications in the automotive and aerospace sectors. Moreover, this review highlights the challenges associated with the fabrication of these composites, such as achieving a homogeneous particle distribution and minimizing porosity. It also discusses the latest advancements in processing techniques aimed at overcoming these challenges. Additionally, this review addresses the potential environmental and economic benefits of using natural reinforcements, which not only reduce material costs but also contribute to sustainable manufacturing practices.

Fracture toughness in SPCC/CFRP hybrid laminates: Mode I and mode II perspectives

Hybrid composites using adhesive joints are gaining popularity in various industries as their various material combinations can create certain advantages. This research focuses on examining the mode I and mode II fracture toughness characteristics of the combined laminate between Steel Plate Cold Rolled Commercial (SPCC) metal and Carbon Fiber Reinforced Polymer (CFRP) composite processed using adhesive bonding. SPCC/CFRP hybrid laminate composites were manufactured with a variety of manufacturing options (A, B, and C) to find the most optimal method using two types of epoxy and cyanoacrylate adhesives, with two different bonding processes: secondary bonding and co-bonding. Fracture toughness values were measured through the Double Cantilever Beam (DCB) test for mode I and the End Notched Flexure (ENF) test for mode II. The test results showed that epoxy adhesives in the SPCC/CFRP adhesive joints provided better fracture toughness performance, especially when combined with the co-bonding technique. Specimens from manufacturing option C showed the highest GIC and GIIC values of 83.05 and 254.94 J/m2, respectively. These values increased by 58.98 % and 80.48 % compared to manufacturing options A and B in Mode I. Additionally, the GIIC value for manufacturing option C increased by 78.00 % and 66.76 % compared to manufacturing options A and B. The SPCC/CFRP hybrid laminates showed adhesive failure on the SPCC surface when using epoxy adhesive, whereas adhesive failure occurred on the CFRP surface with cyanoacrylate adhesive for the different manufacturing options.

Sol-Gel Derived Alumina Particles for the Reinforcement of Copper Films on Brass Substrates.

The aim of this study is to provide tailored alumina particles suitable for reinforcing the metal matrix film. The sol-gel method was chosen to prepare particles of submicron size and to control crystal structure by calcination. In this study, copper-based metal matrix composite (MMC) films are developed on brass substrates with different electrodeposition times and alumina concentrations. Scanning electron microscopy (FE-SEM) with energy-dispersive spectroscopy (EDS), TEM, and X-ray diffraction (XRD) were used to characterize the reinforcing phase. The MMC Cu-Al2O3 films were synthesized electrochemically using the co-electrodeposition method. Microstructural and topographical analyses of pure (alumina-free) Cu films and the Cu films with incorporated Al2O3 particles were performed using FE-SEM/EDS and AFM, respectively. Hardness and adhesion resistance were investigated using the Vickers microindentation test and evaluated by applying the Chen-Gao (C-G) mathematical model. The sessile drop method was used for measuring contact angles for water. The microhardness and adhesion of the MMC Cu-Al2O3 films are improved when Al2O3 is added. The concentration of alumina particles in the electrolyte correlates with an increase in absolute film hardness in the way that 1.0 wt.% of alumina in electrolytes results in a 9.96% increase compared to the pure copper film, and the improvement is maximal in the film obtained from electrolytes containing 3.0 wt.% alumina giving the film 2.128 GPa, a 134% hardness value of that of the pure copper film. The surface roughness of the MMC film increased from 2.8 to 6.9 times compared to the Cu film without particles. The decrease in the water contact angle of Cu films with incorporated alumina particles relative to the pure Cu films was from 84.94° to 58.78°.

Thermolysis of Cs9MO4 (M = In, Sc): Synthesis, Crystal Structure, Chemical Bonding, and Reactivity of the Subvalent Oxidometalates Cs7MO4 (M = In, Sc).

The cesium-poor alkali-metal suboxidometalates Cs7MO4 (M = In, Sc) were prepared from the respective cesium-rich suboxidometalates Cs9MO4 by thermolysis in a dynamic vacuum at temperatures below 150 °C. They crystallize in a new structure type, comprising isolated tetrahedral oxidometalate anions [MO4]5- immersed in a matrix of metallic cesium atoms. This structural separation into alternating ionic and metallic building units is typical for subvalent compounds. Cs7InO4 and Cs7ScO4 are isotypic and form mixed crystals Cs7(In1-xScx)O4 with statistic distribution of In and Sc atoms. All compounds were characterized by single crystal and powder X-ray diffraction. Calculations of the electronic structure with DFT methods corroborate the coexistence of anionic entities within a metallic matrix and give evidence of the subvalent nature of cesium atoms. Overall metallic behavior is a consequence of the equal volume fractions of metallic and ionic regions, allowing for percolation of the conduction electrons throughout the crystal volume. Differential thermoanalysis was employed to gain insight into the chemical conversion processes during the thermolysis reaction. The thermolytic decomposition of Cs9MO4 is a multistep process with, in some instances, reversible amorphization and recrystallization steps. Finally, the formation of ionic compounds is observed. The full decomposition of Cs9ScO4 yields the two new oxidoscandates Cs14Sc4O13 and Cs17Sc5O15 with tetrahedral [ScO4] units connected to chain fragments and the indium compound yields cesium oxidoindates with low-condensed [InO4] building units. The cesium-poor suboxidometalates Cs7MO4 themselves can serve as starting materials for the synthesis of further, new suboxidometalates, as they show a unique reactivity toward metals.

Gray relational analysis for parametric optimization of micro-EDM of thermo-mechanically processed AA7075 and AA7075/SiC/Gr composite

The AA7075 alloy and AA7075/SiC/Gr hybrid composite prepared by the stir-casting method have been further thermo-mechanically processed through unidirectional hot rolling and hot cross-rolling routes to eliminate casting defects like voids, blow holes etc. Three initial sample temperatures, that is, 350℃, 400℃, and 450℃, have been considered for the hot cross-rolling. The Al alloy and its hybrid composite prepared at different rolling temperatures are studied to investigate their micro-machining behavior through micro-electric discharge machining (µ-EDM). The micro-holes are made on the rolled samples along the rolling direction of the final rolling pass using a tool with twist drill bit geometry. Further, multi-objective optimization of the µ-EDM process parameters considering the response parameters viz. material removal rate (MRR) and tool wear rate (TWR) has been carried out using the gray relational analysis (GRA) technique. The µ-EDM parameters chosen to optimize in this study are voltage, pulse on time, and tool rotation. The obtained GRA results are further analyzed through normality and equal variance tests. The R-squared values of 95.02% and 95.53% for AA7075 alloy and hybrid composite, respectively, indicate that the data fit well with the statistical model. In material removal, the different electrical and thermal characteristics of the Al matrix and the reinforcements possibly generate sparks with a different characteristic that ultimately affects the MRR of the composite. Through scanning electron microscopy (SEM), the morphological study confirmed the presence of globules and voids on the machined surface. The formation of globules and voids is more significant in the AA7075 alloy than in the composite.

AgBiS2/g-C3N4 hybrid composites: synthesis, characterization and counter electrode performance in photovoltaic device

AgBiS2/g-C3N4 hybrid composites: synthesis, characterization and counter electrode performance in photovoltaic device

Innovative approach for enhancing thermal diffusivity in metal matrix composites using graphene electrodeposition and multi-coating

Innovative approach for enhancing thermal diffusivity in metal matrix composites using graphene electrodeposition and multi-coating

Evaluation, tribological examination, and multi‐objective optimization of aluminum‐fly ash‐egg shell composites for sustainability

AbstractThis study addresses the technological challenge of enhancing the mechanical and tribological properties of Al 6082 alloy by incorporating fly ash (FA) and eggshell (ES) as reinforcing materials. The objective is to fabricate hybrid metal matrix composites using sand casting, with varying weight percentages of eggshell and fly ash: 4 wt% eggshell with 6 wt% fly ash, 5 wt% eggshell with 5 wt% fly ash, and 6 wt% eggshell with 4 wt% fly ash. The experimental methodology involved designing experiments with response surface methodology (RSM), considering applied load, sliding velocity, and sliding distance as variables. The outcomes showed that the composite with 6 wt% eggshell and 4 wt% fly ash exhibited superior hardness, tensile strength, and impact resistance compared to pure Al 6082 and other composite variations. Additionally, this composite reduced the coefficient of friction (COF) from 0.489 for the base Al 6082 to 0.265. ANOVA based on RSM identified sliding distance as the most influential factor affecting COF. Optimal conditions for minimizing COF were determined to be a 40 N load, 0.215 m/s sliding velocity, and 800 m sliding distance through confirmatory trials. Scanning electron microscopy (SEM) analysis of the worn surfaces provided further insights into the wear mechanisms. The research reveals that integrating the addition of eggshell and fly ash significantly enhances the mechanical properties and reduces the friction of Al 6082, with sliding distance being a critical factor in tribological performance. This investigation is distinctive due to its innovative use of dual reinforcement with fly ash and eggshell, which are abundant, cost‐effective, and rarely employed together in this context. The research thoroughly investigates various reinforcement ratios, providing vital insights into how they affect the composite's properties, particularly in terms of improving tribological properties. Using RSM and ANOVA makes the findings more precise and reliable. The investigation highlights sliding distance as the key factor affecting the tribological behavior of the composites.

Dry sliding wear performance of hybrid composites, comprising AlMg1SiCu alloy, titanium carbide, and molybdenum disulfide fabricated through stir casting process at different temperature condition

Dry sliding wear performance of hybrid composites, comprising AlMg1SiCu alloy, titanium carbide, and molybdenum disulfide fabricated through stir casting process at different temperature condition

Innovation in sustainable composite research: Investigating graphene-reinforced MMCs for liquid hydrogen storage tanks in aerospace and space exploration

The demand for lightweight materials in space exploration applications has seen a significant rise. This study presents a novel approach by integrating graphene with Aluminium alloy (AA) 2900 powder, synthesized through High energy ball milling technique. The resulting powder was used to reinforce Aluminium alloy 2195, creating metal matrix composites (MMCs) via squeeze casting. The findings demonstrate that incorporating 0.5 wt % 2D graphene nanoplatelets (2D-Grnp) in AA 2195 achieved density match, enabling homogeneous dispersion, addressing composite casting challenges. Consequently, the AA 2900 alloy embedded with 2D-Grnp facilitated the homogeneous dispersion of reinforcements during the squeeze casting process, yielding MMCs Ideal for potential use in lightweight liquid hydrogen fuel tank structures for launch vehicles. Following T8 heat treatment, the final casted composite plate exhibited significant enhancements in ultimate tensile strength, with a 4.5% increase over monolithic Al 2195-T8, exhibiting nominal reduction in elongation behavior and higher hardness. Additionally, scanning and transmission electron microscopy (SEM, TEM), Small Angle Neutron Scattering (SANS) and Electron Backscatter Diffraction (EBSD) revealed the squeeze casting technique's effectiveness by exhibiting enhanced bonding among homogeneously reinforced 2D-Grnp, T1/θ’ precipitates, and AA 2195.

Paradigm on Levenberg–Marquardt neural algorithm analysis of heat conduction optimization for ternary hybrid nanofluid with entropy generation

AbstractThe significance of the present article is to enhance the thermal management and energy efficiency of complex engineering infrastructures such as energy storage systems, modern electric vehicles, thermal insulations, heavy‐duty machinery, and production units. This research aims to understand the intricate relationship between the thermal conductivity performance of ternary () hybrid nanomaterial and entropy generation to optimize material design and efficacy. A synergetic combination of three distinct nanomaterials silicon dioxide, ferric oxide, and titanium oxide with ethylene glycol and water in the ratio 3:2 as a base solvent is comprised of contributing unique thermophysical properties. To elucidate the impact of this hybrid composition on thermal conductivity, various factors are analyzed. The advanced computational technique of Artificial intelligent feed‐forward neural network (AIFFNN) is utilized. The problem governed the system of PDEs, which is transformed into ODEs by dimensionless similarity. Adams method provided the dataset which is filtered and embedded into Marquardt–Levenberg Algorithm (LMA). The study examines the role of nanomaterial constituents, morphology, and boundary conditions on thermal performance and entropy generation. Graphical analysis of velocity, temperature, and entropy is provided with respect to varying parameters, including surface absorption (λ), magnetic strength (Tesla M), radiation parameter (Rd), Brownian motion (Br), and Eckert number (Ec). The findings have practical significance for optimizing material design in engineering and industrial applications.

Impact of different parameters in tribological properties of enset ventricosum/ terminalia arjuna fibers /SiO2 filler incorporation

Natural fiber composites have garnered considerable interest in recent years as sustainable substitutes for synthetic materials, owing to their environmental advantages, including renewability, biodegradability, and cost-effectiveness. Notwithstanding these benefits, there is a vital need to improve the mechanical and tribological characteristics of these composites for applications involving significant wear. This work used compression molding to make hybrid composites with natural fibers (NFs) and nano silicon dioxide (nSiO2) filler. The matrix material was epoxy, and the natural reinforcements were Enset ventricosum (EV) and Terminalia arjuna (TA) fibers. Tensile (TS), flexural (FS), and impact (IS) characteristics improved using 1:1 SiO2 filler and EV/TA fiber reinforcement. The combination of 6 wt% SiO2 and 45 wt% EV/TA improved mechanical performance. A high SiO2 filler (6 wt%) in polymer-based composites decreased Specific Wear Rate (SWR), according to Taguchi optimization. A better fiber-matrix interaction improves the mechanical characteristics of materials with fillers. This study optimized several responses using the new combined compromise solution (CoCoSo) method. Multi-criteria decision making is used here. This study introduces Method based on the Removal Effects of Criteria (MEREC) to determine objective criteria weights. Conclusions from experiments show ideal results. CoCoSo's optimization study showed that Enset ventricosum and Terminalia arjuna fiber (EV/TA) hybridization affected composites' tribological behavior.This hybrid fiber combination carried the most influence, followed by fillers. The optimal results were obtained with 6 wt% SiO2/25 wt% EV/TA Hybrid fiber, 1000 m Sliding distance (SD), 2 m/s Sliding speed (SS), and 10 N axial load (AL).

Influence of Prosopis juliflora bark powder/fillers on the mechanical, thermal and damping properties of jute fabric hybrid composites

In recent years, the natural fiber (NF) reinforced composites have become popular as substitute material for conventional metals and alloys in a range of structural applications. The aim of this experiment is to utilize the waste of both Prosopis Juliflora (PJ) bark and Jute fabric in valuable applications for the first time. The influence of fabric stacking patterns on the mechanical characteristics (ductile, flexural, hardness and impact) and thermal stability of fabric Jute/PJ bark powder reinforced hybrid composites in the epoxy matrix is investigated in this task. The compression moulding method is used to create composite laminates of same widths that are layered in various combinations of 5%, 10% and 15% weight of PJ bark powder. The prepared reinforced test samples characteristics of tensile, flexural, impact, and hardness characteristics are experimentally investigated. The outcomes revealed an inclusion of 15 wt% of PJ bark powder reveals positive effect on tensile, flexural, impact, hardness and thermal characteristics. These composites have a diverse range of applications, including industries, automobile and civil applications.