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AMM has developing demand in shipping-aerospace, automobile and various industries due to its low weight, specific strength, corrosion resistance and workability. Particle strengthened AMCs are leading due to their less cost, uniform residences, and their capacity to be like monolithic materials. Although severa strategies are to be had to manufacture the particulate MMCs, stir casting process is the most optimum one because of its price effectiveness and comfort. This research review examines the challenges faced and outcomes achieved by different researchers who have made contributions to the field of stir casting aluminum metal matrix composites with particulate reinforcement. According to published research, the hardness and tensile strength of the composite are increased by adding reinforcement and decreasing the size of the particles by a percentage. Investigations were conducted into the effects of Mo and Sic inclusions on the machinability and microstructural behavior of composite materials. [ABSTRACT FROM AUTHOR]

friction crush welding is one type of friction welding in the solid state (under the melting point of material) that depends on the friction between rotating tools and workpieces generating heat and then softening material to form a weld joint. This process technique is used a lot in the work set industry, automotive, and aerospace. This present work investigated the distribution of temperature of aluminum1050 sheets due to heat generation during friction (tool and workpieces) through the new welding process called friction crush welding technique and studied the effect of rotational speed and welding speed on the temperature at the welding joint. This experimental work used a horizontal milling machine under rotational speeds (1400,1120,900 RPM) and welding speeds (36,16mm/min). A thermal camera was used to measure the variation of temperature on the welding line during the crush welding process. The results showed the maximum temperate was 308°C with a rotating tool speed of 1400 rpm and welding speed at 16 mm/min and also observed the value of temperature increased with the increase of rotating tool speed and decreased with an increase in welding speed during the welding process. [ABSTRACT FROM AUTHOR]

The Importance Performance Analysis (IPA) method is an appropriate tool for analyzing each product attribute which is its strengths and weaknesses, as well as determining the scale of preference of customer needs for the product. The objective of this research is aluminum window products by conducting a survey of 79 customers of aluminum window products using Slovin formula with 90% confidence level.the IPA matrix was applied to see the importance of focus on customer satisfaction needs. As the results, the validity and reliability tests on the performance indicators show the value of which is more than 0.1864 and cronbach alpha value 0.949, where the number is said to be eligible because it has met the specified conditions, while the importance indicator shows the value as more than of 0.1864 and Cronbach alpha 0.873. The result has shown that to be feasible because it has exceeded the minimum limit. In the Cartesian diagram the processing results of the IPA method show that there are 7 attributes that are the main priority to be improved, namely non leaking windows, airtight windows, can be waterproof on high surfaces (installed in tall buildings), can be wind resistant when installed in tall buildings, does not fall when withstanding wind pressure, aluminum profile material mixture is better, the price is more competitive. [ABSTRACT FROM AUTHOR]

In recent times, Aluminum Matrix Composites (AMCs) are most commonly used in many industrial works. For Al6063, easiest technique for the fabrication will be the stir casting method. The stir casting techniqueimporves the homogenity of reinforcement at final stage of the casting which enhances the intended properties of composite materials. However, the stirring effect affects the homogeneity of the particle distribution in the composite is not well studied. Even though Aluminium has been a game changer in creating light weight aircraft durable material. It can further be enhanced for creating a rigid, durable long lasting, light weight compounds. The purpose of this Matrix is to create a better source for light weight exo-skeleton. Exo-skeleton will be a pocket rocket for a military during battles. They will relieve the stress in carring the equipment and weaponry of a soldier for a period of time. The mechanical part of the exoskeleton ie the frame must be durable to with harsh battle conditions and must be wear resistant. By reinforcement with suitable compound the strength and wear resistant properties are enhanced. [ABSTRACT FROM AUTHOR]

Guided wave (GW) propagation is one of the most effective damage identification and Structural Health Monitoring (SHM) techniques. SHM systems can provide numerous benefits in short and long term with respect to inspection and maintenance/repair operations. Typical GW-SHM system employ a piezoelectric (PZT) sensors network to diagnose the state of health of the component, allowing for a quasi-real time monitoring by comparing datasets recorded in two different states of the structure. In this paper, a novel damage detection and localization method is discussed. With respect to the actual state of the art, the developed algorithm can locate damages inside and outside the area covered by the PZTs. To assess its reliability, Finite Element (FE) analyses on an aluminium panel, equipped with five surface bonded sensors, have been carried out. Different damage positions have been analysed. The algorithm effectively works in all test cases, resulting in an image that highlights only the faulty area. [ABSTRACT FROM AUTHOR]

Cracks in engineering structures affect the dynamic characteristics and leads to failure of beam structures over a period of time. The crack will propagate due to vibration characteristics and the resultant fatigue in the beam structures. This paper focuses on a cantilever beam subjected cracks of different depth and its location under free vibration. The effect of such vibrations and crack are analyzed. Different aluminium alloys which find modern application in areas like aerospace, automobile, marine, construction industry etc. are considered for analysis. The change in modal shape and natural frequency of the beam structure due to crack under free vibration analysis is carried out by changing the crack location, crack depth and also the material properties by Finite Element Method (FEM) using ANSYS software. The natural frequency of the beams under test comprising of different Aluminium alloys is compared for various location and depth of crack. The modal shape of the free vibration analysis of the Aluminium alloy beam shows that the crack brings down the natural frequency level and it gets further reduced when the crack depth increases. [ABSTRACT FROM AUTHOR]

This investigation aims to study the mechanical properties and microstructural analysis of aluminium matrix incorporated with different amount of Fe3O4 at (2, 4, 6, 8 and 10) wt.% with constant amount of Ni at 2wt.%. Al/ Fe3O4 +Ni hybrid nanocomposites specimens were prepared using powder metallurgy technique. Aluminium matrix nanocomposites (AMNCs) are considered as an important alloy due to their properties such as high strength, wear strength and light weight which enable them to use in many applications such as automotive, electronics and aerospace. There are many examinations have been carried out for the specimens of this work such as Field Emission Scanning Electro Microscope (FESEM) and X-Ray Diffraction (XRD) analysis to estimate the microstructure and phases of the prepared nanocomposites. Mechanical tests also carried out such as micro hardness test, compressive test and wear test to evaluate the mechanical properties of the hybrid nanocomposites. The results of this work show that Fe3O4 and Ni nanoparticles have been homogeneously dispersed in Al matrix by FESEM and XRD analysis. While the mechanical tests show that improving the compressive strength at 8wt.% by 55.36%, the highest micro hardness at 10% by 111.1% and also improving wear rate. [ABSTRACT FROM AUTHOR]

The type of material is one of the basic requirements for an automotive design. With the various needs of mechanical properties, the types of material are different. Charpy Impact Test is a method that can be used to measure the strength, toughness and ductility of a material. This study is aimed to determine the value of the impact energy and stress with variations of impactor velocity (2 m/s, 2.5 m/s and 3 m/s), the notch on the specimen (v, u and keyhole), impactor's mass (1 kg, 1.5 kg and 2 kg). This research uses finite element method software to develop the models. From the simulation's results, the value of the stress and impact energy obtained is various, namely, the maximum stress of v notch is 369.7 MPa at an impactor velocity of 3 m/s and impactor's mass of 2 kg, the maximum stress of u notch is 371.9 MPa at an impactor velocity of 3 m/s and impactor's mass of 1.5 kg, and the maximum stress of keyhole notch is 370.8 MPa at an Impactor velocity of 3 m/s and impactor's mass of 2 kg. The maximum impact energy for 0.179 J/mm2 at keyhole notch with impactor velocity of 3 m/s and impactor's mass of 2 kg. Therefore, the most difficult model to break is the model with a keyhole notch because it has higher toughness. [ABSTRACT FROM AUTHOR]

The usage of aluminium as an alloy has great demands in the construction, aerospace/aircraft, especially in the automotive sector. Almost all frames and engine construction are made of aluminium alloy. The advantages of aluminium include its lightweight metal, corrosion resistance, good electrical conductor, easy integration with other metals, and machinability. Al-Si alloys in the automotive sector, such as conditional pistons are very suitable because of their wear resistance, corrosion resistance, and lightness properties. This study aimed to identify the effect of adding copper to the Al-Si alloy to obtain the Al-Si-Cu alloy, which was expected to provide mechanical strengthening and microstructure from the stir casting process. The mechanical toughness test results showed an increase in toughness at the addition of 1.5 wt% with a value of 0.0977 J/mm2. Simultaneously, the raw material had a value of 0.0707 J/mm2, gradually decreased with the addition that exceeded 1.5 wt%, namely 2.5 wt% addition resulted in a value of 0.0661 J/mm2, and the addition of 3.5 wt% with a value of 0.0578 J/mm2. The formed microstructure showed continuous smaller granules with increasing Cu percentage, while the dendrites had slender characteristics that increased with increasing Cu percentage. [ABSTRACT FROM AUTHOR]

Due to their low shrinkage and simple mouldability, epoxy resin composites are commonly applied in moulds manufactured with quick tooling technologies. Various percentages of aluminum particles (20 percent, 40 percent, and 60 percent) added by weight with epoxy resin are formed and machined to the ASTM according to cold stir casting. In terms of the Tensile test, Flexural test and Brinell hardness, mechanical properties are defined. A critical parameter, thermal conductivity, is calculated for good service efficiency and mold durability. For better mouldability, the proportion of aluminum and epoxy resin for which the hardness, flexural and thermal conductivity of the composite holds well is calculated. [ABSTRACT FROM AUTHOR]

The phase composition of the surface layer of AlSi10Cu2Ni and AlSi5Cu2 silumins after electron beam processing has been studied by the methods of X-ray phase analysis in the research. It has been detected that in the initial state the main phases of AlSi10Cu2Ni silumin under study is a solid solution based on aluminium, silicon and intermetallides, ones of which are Fe2Al9Si2 and Cu9Al4 phases. The X-ray phase analysis of AlSi5Cu2 silumin samples irradiated by the pulsed electron beam has shown that the main phases of the alloy are also a solid solution based on aluminium, silicon and intermetallides, and Fe2Al9Si2 phase is present. The analysis of aluminium diffraction maximums has shown that they are splitted. This permits one to speak about the existence of two solid solutions based on aluminium being different in crystal lattice parameters and, consequently, the concentration of alloying elements. The first type— solid solution based on aluminium with a larger parameter of crystal lattice Al1; the second type—with a smaller parameter of crystal lattice Al2. The alloys' irradiation by pulsed electron beam is accompanied by the change in crystal lattice parameter of AlSi10Cu2Ni (solid solution based on aluminium) and AlSi5Cu2 (phases Al1 and Al2). Probably, the reason of the change in crystal lattice parameter in AlSi10Cu2Ni and AlSi5Cu2 alloys is the variation in alloying elements concentration in solid solution of the phases. [ABSTRACT FROM AUTHOR]

In the present paper, different numerical analyses are carried out for modelling impact events. Smooth Particle Hydrodynamics (SPH) formulations, Finite Element Method (FEM) and a coupled FEM-SPH models are performed to investigate the response of AA5083-H116 Aluminium plate subjected to low velocity impact (12.31 m/s). Dimensions of Aluminium plate is 300 x 300 x 5 mm. There are 16 types of SPH formulation are available in Ls-Dyna, however, 4 of them are recommended to use with solid structures which are Standard SPH formulation (FORM=0), Renormalized SPH formulation (FORM=1), Total Lagrangian Formulation (FORM=7) and Renormalized Total Lagrangian Formulations (FORM=8). For FEM-SPH modelling, SPH particles are modelled with renormalized SPH formulations. Johnson-Cook material model is used with Gruneisen Equation of State (EOS) for the Aluminium plate. The response to impact event of models contain maximum deflection which is validated by experimental data available in literature. The results show, Total Lagrangian behaviour and FEM-SPH coupling have good agreement with experimental data by less than 2% error. However, maximum deflection value of standard SPH formulations obtained has 18.07% error. [ABSTRACT FROM AUTHOR]

Tremendous researches are progressing on Aluminum Matrix composites to get along with extensive use in applications such as automobile, aerospace, marine etc. The present technology demands affordable reinforcement of industrial wastes to produce composite materials. Recent studies have shown that flyash is one of the industrial wastes for reinforcement along with Aluminum alloys which enhances the mechanical properties. The use of flyash in Aluminum Alloys reduces the density and improves the strength of composites. In the current study, the results obtained from the reinforcement of flyash in A356 alloy for various volume percentage are investigated and enhancement in the mechanical properties of automobile application (Piston) is analysed. Variation of structural properties such as deformation and strain variations are obtained. It is observed from the analysis that total deformation, directional deformation and equivalent elastic strain decreases with the addition of flyash to alloy. It is also seen that as the volume percentage of flyash increases, deformation decreases and the least deformation is observed for A356 Al C12(S) [ABSTRACT FROM AUTHOR]

Within the semi-empirical model of detonation of monodisperse suspensions of micro and nano-sized aluminum particles, two-dimensional flows in channels are studied by numerical simulations. The problems of the propagation of detonation in a plane channel and a channel with a section of linear expansion are considered. The influence of the particle size on the detonation regimes is analyzed. Analysis of the formation of cellular detonation in a flat channel showed that the irregularity of cellular structures manifests itself in the nanometer range, which is due to an increase in the activation energy of the reduced reaction during the transition from diffusion to kinetic combustion of particles. In the expanding channel, the propagation of detonation is characterized by the formation of a system of transverse waves, the regularity of which is related both to the size of the particles and to the magnitude of the expansion angle. The maps of detonation modes are obtained depending on the parameters: the particle size, the expansion angle, and the width of the output channel. [ABSTRACT FROM AUTHOR]

The propagation of a detonation wave in a channel with linear expansion in a two-fractional suspension of aluminum particles in oxygen was investigated. Fractions of particles with diameters 3.5 μm and 1 μm were considered. The verified semi-empirical detonation model was used taking into account transition from diffusion to kinetic regime of combustion of micro-sized aluminum particles. The influence of the fractional composition of the mixture on propagation regimes and formation of transverse waves of cellular detonation is established. [ABSTRACT FROM AUTHOR]

A physical and mathematical model of detonation of aluminum particle gas suspensions of in a wide range of particle sizes from several micrometers to tens of nanometers is presented. In the description of transport properties of particles in the flow and interphase heat transfer, the transition from the continuum regime to the free-molecular regime is considered. The description of aluminum particle combustion is based on the reduced Arrhenius-type kinetics. We take into account the transition from the diffusion type of combustion of large particles to the kinetic type for particles smaller than 1 micrometer. The reaction constants were obtained from the data of experiments on the dependence of the burning time of nano-sized particles on the temperature and pressure of the surrounding gas and the particle diameter. Examples of Chapman-Jouguet detonation structures are given. The boundaries of the applicability of the continual description of thermal dynamics in the detonation of particle suspensions in gas are determined. [ABSTRACT FROM AUTHOR]

An interaction of a detonation wave propagating in the cellular detonation mode with a cloud of inert particles is investigated numerically. The analysis of results allows the regimes of propagation of the heterogeneous cellular detonations and their suppression to be identified. The influence of various parameters of the inert cloud including consideration of nanosized particle ignition and combustion processes is demonstrated. It is shown that the disperse composition and the non-uniform distribution of particles in the cloud are important parameters affecting the detonation propagation mode. [ABSTRACT FROM AUTHOR]

In order to improve the ultrasonic wave amplitude excited by electromagnetic acoustic transducers (EMATs), many researchers have proposed models. But they always ignored displacement current or the effect of the permittivity of the air or the metal sample during modeling, due to its low permittivity. However, more durable dielectric materials are replacing or coating with metals in many applications which have a much higher permittivity than air or metal sample so that the effect of permittivity cannot be ignored. Based on an analytical model, the effect of the permittivity of coating layer on the eddy current generated in an aluminum sample by EMAT has been studied. The analytical analysis indicates that the eddy current density excited by the spiral coil of EMAT slowly increases in the beginning and then decreases rapidly while the permittivity increases, and it has much relation to the thickness of the coating layer and the exciting frequency, which is verified by the simulation result. [ABSTRACT FROM AUTHOR]

Peculiarities of formation and evolution of tweed structures on the surface of high-purity aluminum polycrystalline foils under cyclic tension were studied using an atom force microscope and a white light interferometer. Tweed structures of micron and submicron sizes were found on the foils at different number of cycles. In the range of 42,000 < N< 95,000 cycles destruction of tweed patterns is observed, which leads to their disappearance from the surface of the foils. Formation of tweed structures of various scales is discussed in terms of the Grinfeld instability. [ABSTRACT FROM AUTHOR]

New aluminosilicate filled with aluminum oxyhydroxide (AlO(OH)) is offered as a dielectric substrate (DS) for LED devices. The DS obtained from these substances has high thermal conductivity up to λ = 133.61 W/m×K and its value depends on the amount of AlO(OH) in the DS. Such high thermal conductivity is achieved by the homogeneous distribution of a large number of AlO(OH) nanosized particles in crowns of dendrimer aluminosilicate ensembles. The AlO(OH) particles size is comparable to that of voids between branches in the aluminosilicate crowns. The adhesive strength of the filled alumosilicate (80% of AlO(OH)) applied under a shear on the aluminum plate (its roughness is 11.3 µm) is 47 N/mm2 . [ABSTRACT FROM AUTHOR]

In this paper we use eddy currents to determine the depth of linear cracks in aluminum plates. A constant field probe is used to generate the spatially uniform excitation field and a single axis giant magneto-resistor (GMR) sensor is used to measure the eddy currents magnetic field. Different depths were machined in one aluminum plate with 4 mm of thickness. By scanning those cracks the magnetic field components parallel and perpendicular to the crack's line were measured when the eddy currents were launched perpendicularly to the crack's line. To characterize one crack in a plate of a given thickness and material, the experimental procedure was defined. The plate surface is scanned to detect and locate one crack. The acquired data enables the determination of the crack's length and orientation. A second scanning is performed with the excitation current perpendicular to the crack and the GMR sensing axis perpendicular and parallel to the crack's line. [ABSTRACT FROM AUTHOR]

NASA uses high-emissivity surfaces on deep-space radiators and thermal radiation absorbers in test chambers. Aluminum honeycomb core material, when coated with a high-emissivity paint, provides a lightweight, mechanically robust, and relatively inexpensive black surface that retains its high emissivity down to low temperatures. At temperatures below about 100 Kelvin, this material performs much better than the paint itself. We measured the total hemispheric emissivity of various painted honeycomb configurations using an adaptation of an innovative technique developed for characterizing thin black coatings. These measurements were performed from room temperature down to 30 Kelvin. We describe the measurement technique and compare the results with predictions from a detailed thermal model of each honeycomb configuration. [ABSTRACT FROM AUTHOR]

Simulations with reduced kinetic models are used to study shock ignition and detonation in reactive materials that may support non-classical detonation. Porous aluminum Teflon oxidizer mixtures that support combustion reactions in air are considered, as a member of a class of materials with intrinsic interest. We recast a phenomenological theory [4] with realistic kinetics with end products whose primary components are AlF3, CO, CO2 and Al2O3. Intermediate products include at least thirty elementary reactions; a sub-set can be selected to simplify, but a hard problem remains. Results of the multi-species evolution and its impact on rapid self-oxidizing combustion and possible detonation conditions and the computational methods are presented. [ABSTRACT FROM AUTHOR]

We present a novel scheme for monitoring the transition between deflagration and "detonation-like" behavior of small-scale explosive samples subjected to shock stimuli. The intended geometry for this setup incorporates a laser-driven-flyer impact technique to generate a pure mechanical input. However, we report results here using a simplified geometry for purposes of evaluating the time-of-flight mass spectrometric (TOFMS) diagnostics using direct laser ablation of solid aluminum and of an aluminum mirror coated with a small amount (~1 μg) of PETN. This manuscript presents the TOFMS detection of fast aluminum atoms (>10 km/s) resulting from laser ablation, confirming our ability to detect hyperthermal species. Preliminary results from pentaerythritol tetranitrate (PETN) experiments reveal a transition from species consistent with deflagration (primarily NO2) at low laser fluence, to those consistent with detonation-like events (N2, CO, CO2) at higher laser fluence. At this time, due to several unknown parameters in the current setup, we will not posit the exact physical details which cause this transition (e.g. shock pressures, temperatures, etc.). However, these results indicate that such a transition can be detected using the Benchtop Energetics TOFMS diagnostics setup, where future, more controlled and/or characterized energetic events may lead to better understanding of initiation/ignition thresholds of candidate materials. [ABSTRACT FROM AUTHOR]

Nanocrystalline Al3+ ions doped Mg0.2Mn0.5Ni0.3AlyFe2-yO4 compositions, where y=0.0 and 0.10 have been synthesized by citrate precursor method. Crystal structure and magnetic properties have been investigated at room temperature by means of X-ray diffraction, TEM, LCR meter, VSM and Mössbauer spectroscopy. Particle size and lattice parameter has been found to decrease as non-magnetic Al content increased. Relative loss factor has very low value in range of 10-6-10-5 which is three orders of magnitude less than samples prepared by conventional method. The Mössbauer spectroscopy results shows superparamagnetism. The isomer shift corresponding to Fe3+ ions do not show any significant variation which indicates that replacement of Fe3+ ions do not affect significantly the d-electrons density which in turn affects the s-electrons density around Fe3+ nuclei. The nuclear hyperfine magnetic fields have been found to decrease at A-site and B-site with increasing substitution of Al3+ ions in Mg-Mn-Ni ferrite. [ABSTRACT FROM AUTHOR]

Tris-(8-hydroxyquinoline) (Alq3) has been synthesized by simple precipitate method. As-prepared Alq3samples were exposed to Sunlight for various durations under ambient conditions. The Fourier Transform Infrared (FTIR) spectrum confirms the formation of quinoline in as-prepared Alq3 sample. The sunlight exposed Alq3 sample shows the presence of carbonyl group along with the quinoline band. The band gap (HOMO-LUMO) of sunlight exposed Alq3 samples were calculated using absorption spectra and it is around 2.97 eV. The photoluminescence (PL) spectrum of Alq3 particle exhibits a green emission at 507 nm when excited at 390 nm. The Alq3 samples exposed by sunlight reveal the luminescence intensity decreases with increasing exposure to Sun. [ABSTRACT FROM AUTHOR]

Synthesizing nano-particles with narrow size distribution in the gas phase process, via thermal plasma reactor is a challenge. The paper addresses this problem by introducing a crucial modification in thermal plasma reactor, used to produce nano-aluminum particles for propellant applications. The size distribution is assessed by transmission electron microscopy. [ABSTRACT FROM AUTHOR]