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Metal matrix nanocomposites have received more focus in the last two decades because of their desirable alternative features. Many researchers have made several attempts to identify the suitable nanoreinforcement particles for getting improved results in various applications. Many of them tried to improve the properties of several metal matrix nanocomposite materials including mechanical properties, electrical properties, barrier properties, structural properties, moisture permeability, etc., with the help of a variety of techniques. Research study results revealed that the addition of nanosized reinforcement particles improved the mechanical and wear characteristics of aluminum-based metal matrix composites. Metal matrix nanocomposites are being employed in many application areas such as in biomedical field, self-cleaning marble coating application, antimicrobial application and wear-resistant coating application. This review workhas gone through a bulk of research works related to metal matrix nanocomposites. The entire study has been grouped under a few major categories such as synthesis of nanocomposites, characterization study on various nanocomposites, application areas of various nanocomposites, optimization works carried out on nanocomposites, and risk management of nanocomposites. [ABSTRACT FROM AUTHOR]

Hybrid metal matrix composites are gaining more importance in recent years. In this current investigation, aluminium alloy (AA7075) composites have been prepared with nano tungsten carbide (WC) and molybdenum disulfide (MoS2) as reinforcements using stir casting method and investigated. The nano tungsten carbide particles were added into the matrix in the proportions 0%, 0.5%, 1%, 1.5% and 2%, and molybdenum disulfide was added in the constant proportion of 5 wt.% to the molten metal. The prepared Al-hybrid composite samples were tested for their hardness, compression and tensile strength. Microstructure examination has also been performed to understand the distribution pattern of nano tungsten carbide and molybdenum disulfide particles in the base matrix by scanning electron microscope. From the results, it was found that there was steady improvement in composite properties when compared with the base metal while adding WC and MoS2. Thus, the prepared AA7075/MoS2/WC composites were guaranteed for high strength, hardness and exceptional microstructure stability. Dry sliding wear behavior on AA7075/MoS2/WC composites was investigated with the aid of pin-on-disc apparatus. Grey Relational Analysis tool was employed to identify the optimal setting of process variables, which results in lower wear rate and COF. The significance of factors such as sliding distance, sliding velocity and load on the wear characteristics was investigated by means of ANOVA. ANOVA results unveiled that load was the majorly influencing factor in attaining optimal wear characteristics. The tested samples have been investigated using scanning electron microscopy and reported. [ABSTRACT FROM AUTHOR]

Technology advancements are growing in an exponential rate. Automobile sector is getting developed day by day where modern innovations are viewed with different features for the human society. Inspite of having various renewable energy sources, the demand for the fossil fuels still exists for meeting out the requirements of the growing application sides. In the present work, different blends of Curcuma longa waste neat oil samples have been prepared and mixed with diesel at different volume fractions. Nano metal oxide particles such as cerium oxide and Nano Egg Shell Powder (NESP) have been added with the prepared fuel samples in order to achieve better evaporation, atomization, better air-fuel mixing, considerable reduction in ignition delay and best flame sustainability nature. The prepared waste oil samples have been tested under four different loading conditions such as 30, 60, 90 and 120 N. The performance characteristics such as Brake Thermal Efficiency (BTE), Brake Specific Fuel Consumption (BSFC), Exhaust Gas Temperature (EGT), % of carbon monoxide emission, % of carbon dioxide emission, % of hydrocarbon emission and % of NOX emission have been measured for the tested blends. From the results, the optimal sample which exhibits improved desirable characteristics has been suggested. Grey Relational Analysis (GRA) has also been used as a multi objective optimization tool in order to find out the best composition of the Curcuma longa waste oil – diesel blend in order to achieve better desirable properties. ANOVA technique has been used to identify the most influencing input factor in achieving better characteristics for the oil blends.

The present study highlights the formability of hybrid nanofiller modified Glass Reinforced Laminate (GLARE) laminate, by considering the formability index, anisotropic characteristics, and surface crack length, which represent the considerations of forming capability, inherent material property, and damage tolerance, respectively. The GLARE laminates were manufactured by using hybrid fillers, multi‐walled carbon nanotube/nanoclay (MWCNT/NC), and multi‐walled carbon nanotube/Mg‐Al layered double hydroxide (MWCNT/Mg‐Al LDH). The formability analysis was carried out through the results of tensile test and Erichsen cupping test. The anisotropy of the laminate was accounted by considering the parameters, normal anisotropy, and planar anisotropy. The microscopic analysis was performed after the formability test to measure the surface crack length to interpret the forming response of the laminate with hybrid fillers. Desirability function approach (DFA) was applied to prioritize the laminates against the formability index, the anisotropy characteristics, and surface crack length. The results showed that the GLARE laminates with single filler are more suitable for forming operations than the laminates with hybrid fillers. The nanofillers with mixed morphology induced brittleness in the binder. Among the laminates with hybrid fillers, the combination of MWCNT/Mg‐Al LDH exhibited improved compliance with the forming operation. Nanofillers modified adhesives used in the fabrication of GLARE laminates proved to enhance the mechanical properties of laminates. The results of the present study showed an insight into the formability of the laminate. The understanding about the formability of GLARE laminate enables the designer to design automotive and aircraft lightweight structures. [ABSTRACT FROM AUTHOR]

In this experimental research work, the metal matrix composites of A356 alloy were prepared by reinforcing different shaped particles Aluminium Nitride (AlN), Multi-Walled Carbon Nano Tube (MWCNT) and graphite (Gr). The main objective of this research work was to investigate the influence of different shaped reinforcement in the microstructure and mechanical behaviour of composites. The reinforcements (AlN & MWCNT) were added as 0.5, 0.75, 1 and 2 vol% and the graphite was maintained in 0.5 vol%. The composites were fabricated using stir casting followed by ultrasonic vibration treatment. The tensile, compression and Brinell hardness test were carried out by following ASTM standards. The characterization of reinforcements, castings and fractured surfaces was performed using Optical Microscope (OM) and Scanning Electron Microscope (SEM). The mechanical tests and characterization results revealed that there was a significant influence of morphology of reinforcements on mechanical properties of the materials. Particle strengthening and grain refinement strengthening were found to be operative in the composites. The SEM micrograph of fractured surface of composites with MWCNT exhibited the crack bridging effect as strengthening mechanism apart from particle strengthening. The porosity and cluster of reinforcements were observed in the composites with MWCNT more than 1 vol% of and AlN 0.75 vol%.

Due to the advancement in the material technology to produce desired materials for various industrial applications and fast changing scenario in the production of lighter and stronger materials, composite materials are gaining wide acceptance because of their unusual characteristics of behaviour with their high strength to weight ratios. The most widely used material in the current industrial sectors is aluminium and its alloys because of their light weight. To make use of the advantages of the alloys of aluminium for further versatile and flexible varieties of application, such materials are expected to behave as highly resistant to the various loading conditions for a long duration under different environments. Aluminium Alloy 356 has been chosen for the proposed study. AA356 alloy material has been mixed with Zirconium Silicate particles (ZiSO4) with different fractions like 0 wt%, 3 wt%, 5 wt% and 8 wt%. The test samples have been prepared by means of stir casting process. SEM images have been taken on the ZrSiO4 particles for noting down the size and shape of the particles. Three specimens for each composition have been prepared with ASTM standards in order to carry out the tensile test, compression test and hardness test. The tensile test results revealed that AA356 + 5 wt% of ZrSiO4 composition yielded better tensile strength value (169.29 MPa) than the other three compositions. The micro images taken on the fractured samples of the tensile test specimens have been analyzed. It has also been noted that adding ZrSiO4 particles beyond 5 wt% decreased the tensile strength of the proposed composite material. Similarly compression strength and hardness values also have been noted as better upto 5 wt% inclusion of ZrSiO4 particles. [ABSTRACT FROM AUTHOR]

Optimization is ruling the entire field of machining and material processing technology from the time at which the revolution took place in machining processes. Various types of machining algorithms have been developed so far for optimizing the independent control factors in order to get the improved results of desirable output responses. Each algorithm has its own special features which made them useful in deriving the optimized solutions under different conditions. Suitable algorithm is chosen for the required case depending upon the nature of the problem, the requirement of the order of precision and the availability of optimization tools. In this review article, the general flow of few important algorithms has been explained in a simpler manner to be understood by the recent researchers. Also, required numbers of case studies for each algorithm have been provided extensively. This consolidated work will surely be helpful for the new researchers those who have entered into the domain of optimization. [ABSTRACT FROM AUTHOR]

The ultrasonic-assisted stir-casting technique improves the uniform dispersion of nano-reinforcements in aluminum hybrid metal matrix composites. In the present study, the process parameters of the ultrasonic-assisted stir-casting method, such as ultrasonic vibration time, and depth of ultrasonic vibration along with the speed of mechanical stirrer, are optimized on A356 hybrid composite material optimally reinforced with aluminum nitride, multiwalled carbon nanotubes, graphite particles, and aluminum metal powder using the desirability function approach. The process parameters are optimized against the response factors such as porosity, ultimate tensile strength, and wear rate of the composites. The optimum combination of input factors is identified as stirring speed (600 r/min), ultrasonic vibration time (2 min), and depth of ultrasonic vibration (40 mm) among the selected range. The corresponding output response values are found to be porosity (1.4%), ultimate tensile strength (247 MPa), and wear rate (0.0013 mm3/min). The ANOVA results have revealed that depth of ultrasonic vibration showed significant contribution among the input factors. An artificial neural network model is developed and validated for the given set of experimental data. [ABSTRACT FROM AUTHOR]

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Grewia damine is a flowering plant found in India and Sri Lanka. The fiber taken out from the stem bark of G. damine is found to be novel and selected for characterization study. The G. damine stem bark fiber (GDSF) has rich in cellulose contents (57.78 ± 3.56%). Its lower density (1.378 ± 0.036 g/cm3) makes it fit for use in lightweight applications. The weight percentage values of the chemical constituents confirm the use of GDSF for structural applications. Crystallinity index of GDSF was noted as 30.35%. The mechanical properties of GDSF were predicted as 375.6 ± 16.58 MPa tensile strength and 126.2 ± 11.93 GPa modulus of elasticity. The morphological and atomic force microscopy study results revealed that the fiber has rough surface even in its raw form. Hence it can be used to prepare composite specimens with better bonding strength between fiber and polymer. The thermal stability of GDSF was noted as 326 °C. Weibull distribution plots were drawn for validating the physical and tensile property values of GDSF. [ABSTRACT FROM AUTHOR]

The foremost intention of this work is to test the suitability of the Ficus religiosa Root Fiber (FRRF) as the better reinforcement for the natural fiber-reinforced composite structures. In the current work, the attempts have been made with the view of improving the physical, thermal, chemical, surface, and crystalline properties of FRRF employing 5 wt% of NaOH solution. Five samples of FRRF have been prepared by soaking the raw fiber in the alkali solution under different soaking times. The thermogravimetric analysis results reveal that the alkali-treated FRRF soaked for 60 min holds a maximum range of thermal stability (improved by 9.54%); in turn, the remaining analyses have been carried out with that fiber samples. The increased quantity of cellulose contents was witnessed over the surface of treated FRRF. The improvement in the CI from 42.92–48.64% was noted as the result of X-Ray Diffraction test. The morphology study results ensured that the surface of the treated FRRF became so rough comparably, which confirms the removal of unwanted wax and impurities on the fiber surface. All the above observations validated that the proposed fiber is suitable to prepare the composite structures after the optimal alkali treatment. [ABSTRACT FROM AUTHOR]