Grade Aluminum Research Articles

Biogasoline production by zeolite-A catalyzed co-pyrolysis of torrefied cassava root and palm oil

In this study, cassava root was subjected to torrefaction pretreatment prior to catalytic pyrolysis, with the main objective to investigate the effect of torrefaction time on chemical composition of bio crude oil (BCO) distillate resulted. For this purpose, the root was torrefied at 200°C for 30, 60, 90, and 120 minutes. The torrefied samples were then mixed with palm oil and then pyrolyzed at 450 °C in the presence of zeolite-A, prepared from rice husk silica (RHS) and food grade aluminum foil, as catalyst. A sample without torrefaction was pyrolyzed in a similar condition for comparison. The bio-crude oil (BCO) obtained was distilled at 150 °C, and the chemical composition of the distillate was determined using gas chromatography-mass spectrometry (GC-MS) method. The components of the distillates produced from torrefied samples are composed of mainly C6-C13 hydrocarbons, which are considered as biogasoline, while that produced from the sample without torrefaction was found to contain ketone in addition to hydrocarbon. The experimental results also demonstrate that the chemical compositions of the BCO distillates produced from the samples torrefied at 30, 60, and 90 minutes are not significantly different, but significantly different composition was observed for the sample torrefied at 120 °C.

Effect of process parameters on tensile strength of Friction stir welded butt joints of thick AA1350 aluminum plates using Taguchi experimental design

Abstract The requirement for defect free welding for critical applications has resulted in continuous development of advanced material joining processes. Friction stir welding (FSW), a solid state welding process has been accepted for joining of a diversity of materials viz aluminium, copper and other low melting point alloys. This mechanical way of joining is also a proven technique that is being used for joining of dissimilar materials efficiently. In this paper, the FSW has been utilizing for joining of thick aluminium plates to widen the industrial application of FSW. The spindle rotational speed, travel speed of tool and tilt angle of the tool were taken to study their effect on the tensile strength of FSW weld joint. The AA1350 grade aluminium plates having 12.7 mm thickness was taken as the work material for joining. Experimentation was carried out according the Taguchi’s L9 orthogonal array. The lowest level of spindle rotation, and highest level of travel speed and tilt angle of tool were obtained as optimal input variables for desired tensile strength of the joint. The confirmation experiments were also done to validate the optimal settings.

Synthesis of zeolite-Y from rice husk silica and food grade aluminum foil using modified hydrothermal method

In this investigation, zeolite-Y prepared from rice husk silica (RHS) and food grade aluminum foil using modified hydrothermal method. In this proposed method, rice husk silica was dissolved in sodium hydroxide solution to obtain sodium silicate solution and then small pieces of aluminum foil were directly mixed with silicate solution, producing zeolite precursor in the form of gel. The gel was transferred into PTFE lined autoclave and aged for 24 hours and subsequently subjected to the crystallization process for 24, 48, 72, 96, and 120 hours at fixed temperature of 100°C. The solid product was washed with distilled water and dried in an oven at 80°C and calcined at 550°C for 6 hours. Characterization using XRD and SEM confirms the formation of zeolite-Y, and showed that crystallization time influenced both structure and surface morphology of the zeolites quite significantly.

Optimizing the underwater friction stir welding parameters to enhance the joint strength of armour grade aluminium alloy AA5083 butt joints

Solid states prove to justify the existence of joints. The Friction Stir Welding process (FSW) is auspicious in the realm of aluminium composites. The challenge exists in the usage of an FSW for joining aluminium alloys. In this area, a lot of progress is made in the recent years. The underwater FSW procedure (UWFSW) is considered to be one of the most important professional methodologies. It is a totally innovative and futuristic mechanization. Here, the non-expendable electrodes work on the substrate underwater without exhalations. It also requires minimal power, which contributes to enhanced mechanical characteristics. There are many principal advantages such as minimal contortion, non-existence of thaws connected to the imperfections, and the enhanced joining ability. The implement designs and the substance contribute to the enhancement of significant characteristics, including the welding and rotational speeds and equidistant forces. In this research, armour grade aluminum alloy AA5083 with dimensions of 150×100×6.35 mm were friction stir welded under water, in order to improve the joint strength. The results indicated that the tensile strength improved up to 191.3 MPa. The superior granule arrangements, elevated dislocation thickness, and firm elucidation intensification significantly improved the hardness in the minimum hardness location (MHL). This resulted in further improvement of the UWFSW’s tensile strength. The high dislocation density and the elongation were found to probably decrease between NZ and TMAZ.

Fracture behaviour of friction stir welded dissimilar aluminium alloys

High strength aerospace grade aluminium alloys are considered difficult to be welded by conventional fusion welding processes but Friction stir welding (FSW) process can effectively join these alloys with good joint properties. FSW is being widely used in aircraft construction and tank of space shuttles. After successful joining of Aluminium alloys by FSW, the fracture behavior of the joint need to be investigated for analyzing the joint fracture. In the present paper, dissimilar aluminium alloys were welded successfully at a rotational speed of 710 rpm, traverse speed of 160 mm/min and tool shoulder diameter of 12 mm. The welded joint was tested on tensile testing machine and the fracture location was found to be at heat affected zone (HAZ) of advancing side. HAZ was found to be the weakest portion of the joint due to thermal softening which resulted in grain growth and large-sized coagulated precipitates. Cracking of large-sized coagulated Al2Cu precipitates resulted in the fracture of the welded joint.

Experimental observations and data analysis of a commercially grade aluminium alloy (6082T6) for large elastoplastic deformation

Large elastoplastic deformation generally occurs in sheet-metal forming processes during stretching, blanking, punching, stamping, bending, bending-unbending, reverse bending and deep drawing. In today’s world, due to very high competition and swift development of products in metal forming industries, there is a growing demand in high precision end products to be manufactured in short duration. It is very essential and important to have a knowledge of an in-depth understanding of material behaviour in all these metal forming steps. Therefore, to predict material behaviour, an accurate material modelling is required by considering the simultaneous effects of strain and strain rate. Classical flow rules are generally used to predict the material behaviour in the post yield range. Overall material deformation can be represented as the change in size, change in shape and their rates. A new generalised relation is developed to represent the material behaviour from elastic range to failure. This relation involves eight material parameters which includes two classical material constants like bulk modulus and shear modulus, two material viscosity terms and four in the form rule which relates elastic strain rate to plastic strain rate. All these material parameters can be obtained from uniaxial tension experiments. The material deformation is 3-D in nature and therefore classical yield criteria is avoided while formulating the relation. Instead, concept of activation energy is used. In the present work, experimental observations and data analysis on the commercial grade aluminium (6082T6) was discussed. The material behavior in the post yield region with new understanding of the material model was presented here for uni-axial loading case. Based on the experimental observations and the results obtained it was found that the both the elastic moduli and the viscosities remain constant throughout the large deformation.

Development and certification of chromic acid-free anodizing process for aircraft grade aluminium alloys

Chromic acid (Cr 6+ ) anodization process is widely used for the corrosion protection of aircraft aluminium alloys. Hexavalent chromium being toxic in nature need to be phased out by eco-friendly alternatives. In the present study modified tartaric-sulphuric acid (TSA) process has been developed followed by sealing in permanganate based bath to obtain 4 to 6 µm thick anodic oxide layer on 2024-T3, 6061-T6 and 7075-T6 aluminium alloys. The process was carried out using a pilot scale anodizing plant. The anodized specimens were characterized for visual observation, thickness, adhesion, electrical breakdown voltage, corrosion resistance and tensile behaviour. All the tests were carried out as per MIL-A-8625F specifications. The specimens were also subjected for about 800 hrs to real time corrosion testing, 200 metres away from sea shore at Mandapam Camp, Rameshwaram, India. The performance of the permanganate sealed TSA anodized aluminium alloys are comparable with that of the conventional chromic acid anodized coatings. This chromic acid-free anodization process has been qualified to airworthiness regulating standards by Indian military certification authorities. Efforts are in progress to commercialize this technology for use on aero platforms.

Process Parameters Optimization of Pin and Disc Wear Test to Minimize the Wear Loss of General-Purpose Aluminium grades by Taguchi and simulation through Response Surface Methodology

Process Parameters Optimization of Pin and Disc Wear Test to Minimize the Wear Loss of General-Purpose Aluminium grades by Taguchi and simulation through Response Surface Methodology

Process Parameters Optimization of Pin and Disc Wear Test to Minimize the Wear Loss of General-Purpose Aluminium grades by Taguchi and simulation through Response Surface Methodology

Process Parameters Optimization of Pin and Disc Wear Test to Minimize the Wear Loss of General-Purpose Aluminium grades by Taguchi and simulation through Response Surface Methodology

Effect of FSW process parameters and tool profile on mechanical properties of AA 5082 and AA 6061 welds

In the present paper, similar and dissimilar combinations of AA 5052 and AA 6061 Aluminum grades were joined using FSW to obtain desirable mechanical properties. Modified HSS tool containing 10% cobalt with taper pins of circular and trapezoidal cross sections are developed to obtain FSW sheet joints. Process parameters are selected same for both the pin profiles for obtaining weld joints of similar and dissimilar combinations. Welds were obtained at tool rpm of 1600 and 2600 with feed of 15 mm/min. and 20 mm/min. Tensile and hardness properties of AA 5082 and AA 6061 weld joints were analyzed by tensile test and hardness test respectively. It was observed that the taper pin with square tip has produced better mechanical properties in similar and dissimilar weld joints.

Numerical Modeling the Effects of Chamfer and Hone Cutting Edge Geometries on Burr Formation

A finite element based numerical model to simulate orthogonal machining process and associated burr formation process has been developed in the presented work. To incorporate simultaneous effects of mechanical and thermal loadings in high speed machining processes, Johnson and Cook`s thermo-visco-plastic flow stress model has been adopted in the conceived numerical model. A coupled damage-fracture energy approach has been used to observe damage evolution in workpiece and to serve as chip separation criterion. Simulation results concerning chip morphology, nodal temperatures, cutting forces and end (exit) burr have been recorded. Model has been validated by comparing chip morphology and cutting force results with experimental findings in the published literature. Effects of cutting edge geometries [Hone and Chamfer (T-land)] on burr formation have been investigated thoroughly and discussed in length. To propose optimum tool edge geometries for reduced burr formation in machining of an aerospace grade aluminum alloy AA2024, numerical analyses considering multiple combinations of cutting speed (two variations), feed (two variations) and tool edge geometries [Hone edge (two variations), Chamfer edge (four variations)] have been performed. For chamfer cutting edge, the “chamfer length” has been identified as the most influential macro geometrical parameter in enhancing the burr formation. Conversely, “chamfer angle” variation has been found least effecting the burr generation phenomenon.

Выбор режимов сварки при сборке различных материалов по клеесварной технологии

General requirements for change of welding conditions in case of the replacement of the welding tehnology by the glue-welding one have been examined. Conditions of making the glue-weld joints of different grades of steel and aluminum were determined. It was found out that the glue-welding technology required a decrease in the value of welding current and an increase in welding time and the compressive force value of electrodes. A selection of conditions depends on material of jointed components and do not depends on a type of glue material. The study results are presented.

Effect of process parameters on temperature and force distribution during friction stir welding of armor-marine grade aluminum alloy

This research investigates the effect of process parameters on real-time temperature and forces distribution during friction stir welding of AA7039. Experiments are conducted at different rotational speed, welding speed, and tilt angle conditions. For the experimentation, a low-cost real-time force-measuring fixture is indigenously developed in-house. However, eight K-type L-shaped thermocouples are used to examine the real-time temperature distribution. The forces in the z-direction are of a higher magnitude than the x-direction. The maximum force in the z-direction of 3.25 kN is witnessed for 2° tilt angle and a minimum of 2.1 kN for 26 mm/min of welding speed. The maximum force in the x-direction of 0.97 kN is obtained at 2° tilt angle and a minimum of 0.27 kN is obtained at 1.3° tilt angle. The maximum temperature of 390 °C is observed at 1812 r/min, whereas a minimum of 283 °C is observed at 43 mm/min of welding speed. The variations in temperature and force distribution during friction stir welding are also evaluated by utilizing two phenomenological models.

A quantitative structural characterisation of active semiconducting materials (mSi; SiO2; Al2O3; TiO2) for use in printed electronics using a combination of Small Angle Light Scattering (SALS) and Ultra Small Angle X-ray Scattering (USAXS)

Four nanostructured active semiconducting materials currently used in electronic inks have been structurally characterised using a combination of small angle scattering techniques and scanning electron microscopy. The percolation theory and scaling laws have been used to obtain quantitative correlations of the network topologies and the local micro-structures with the electronic and electrical properties of the printed, electronic devices.The small angle light scattering has been used to expand the lower q-range of the Ultra Small Angle x-ray Scattering curves of the 2503 metallurgical grade silicon (mSi), silicon dioxide (SiO2), aluminium dioxide (Al2O3) and titanium dioxide (TiO2) materials by close to an order of magnitude, thereby providing valuable clustering properties for each material. Each scattering curve presented a series of multiple structural levels, which are then quantified using the Unified power-law approach to provide valuable clustering characteristics such as the degree of aggregation, polydispersity and geometry standard deviation. Subsequently, a fully screen-printed field effect transistor that uses mSi as the active material is demonstrated. The transistor had an ON/OFF current-ratio of 104; an electron mobility of 0.7 cm2/V s; a leakage current in the order of 5 × 10−9 A, and no current saturation.

Understanding novel gap-bridged remote laser welded (RLW) joints for automotive high-rate and temperature applications

This paper investigates the microstructure, high-rate and temperature dependent tensile behaviour of fillet edge joints produced by novel ‘gap-bridged’ remote laser welding (RLW) using an automotive grade aluminium alloy AA6014, commercially known as AC-170PX, extensively used for automotive skin panel applications. Three part-to-part gap-bridged RLW fillet edge welds, produced with different gaps (0.2 mm, 0.4 mm and 0.6 mm) were examined for joint geometry and microstructure. Relatively larger columnar grains resulting from directional solidification were observed in the fusion zone and microhardness was reduced by ~15- 20% due to precipitates disappearance. Moderate (0.1 m/s) to high speed rate (10 m/s) tensile tests performed at room temperature (~23°C) were used to determine high-rate tensile performance. Although the strain rate dependency was found to be low, an increase in tensile extension was obtained. Additionally, the joint tensile performance was evaluated over a range of temperatures between -50°C and 300°C. Using digital image correlation (DIC), fracture strains were obtained in the range from 0.21 to 0.25 for all gap and speed conditions. Fusion zone based finite element simulations were performed using the Johnson-Cook material failure model to predict joint strength. Additionally, the suitability of gap-bridged RLW joints for automotive applications was determined by comparison with two industrial joining methods, self-piercing riveting (SPR) and resistance spot welding (RSW).

Chest shielding in preterm neonates under phototherapy-a randomised control trial.

Shielding the precordium can effect manifestation of haemodynamically significant patent ductus arteriosus (hsPDA). Preterm neonates born at ≤ 32weeks of gestation if needed phototherapy within 72h of birth and had no echocardiographically proven hsPDA were eligible to be enrolled in this open-label randomised controlled trial. In chest shielding group, in addition to the standard care, left side of the chest was covered using food grade aluminium foil during phototherapy while control group received standard care. Mean gestational age (weeks; 30.1 ± 1.5 vs 30.1 ± 1.6) was comparable in the two groups. However, neonates in the chest shield group had lower birth weight (g; 1281 ± 259 vs 1422 ± 307) and were more likely to be small-for-gestational age (21.6% vs 8.0%). It was seen that 4 (7.8%) babies in the chest shield group and 5 (10%) babies in the standard group developed hsPDA after starting phototherapy with relative risk (RR) of 0.78 (95% CI 0.22-2.75). The left atrium to aortic ratio was significantly different in the two groups with 1.5 ± 0.1 in the chest shield group and 1.8 ± 0.2 in standard group (p value 0.03).Conclusion: Chest shielding of preterm babies during phototherapy has no effect on the incidence of haemodynamically significant patent ductus arteriosus.Trial registration: Trial was registered with Clinical trial registry of India (CTRI/2018/01/011069). What is Known: • Chest shielding in preterm neonates under phototherapy has inconclusive effect on the manifestation of patent ductus arteriosus. What is New: • Preterm neonates under phototherapy have no significant difference in manifestation of haemodynamically significant patent ductus arteriosus if precordium is shielded.

Modeling of friction stir welding of aviation grade aluminium alloy using machine learning approaches

ABSTRACT The machine learning methodology is gaining immense exposure as a potential methodology for solving and modeling manufacturing problems. The present study deals with the application of machine learning approaches in analyzing and predicting the tensile behavior of friction stir welded AA6082. Rotational speed and feed rate are used as input variables; ultimate tensile strength (UTS) is observed as a response parameter. Full factorial designed is used to perform the experiment. Random forest regression, M5P tree regression, and artificial neural network (ANN) are employed to validate the experimental results. These machine learning-based models are adopted to analyzing the absurdity in actual and predicted data. Random forest regression is observed best performing a machine-learning approach in predicting the tensile behavior of FSW joints. In addition, sensitivity analysis is also carried out to determine the most sensitive factor for UTS. It is observed that rotational speed is the most influencing factor for UTS.

Comparative study of tungsten inert gas and friction stir welding of aluminium alloy aa5083 (armour grade) aluminium alloy joints

Aluminium-magnesium Alloy AA5083 is used widely as a building and tooling material in aerospace, automobile, and marine industries. This Work shows the comparison of AA5083 (armor grade) – 6mm thickness plate weldments mechanical properties on TIG Welding and FSW processes. Welding of metals is based upon the input parameters as it has an important role of finalizing the weldment and the tool used for welding is H13 Tool Steel as the tool has less deformation due to high chromium content. Generally, the welding processes are aimed at achieving a welding joint with superior mechanical properties with minimum deformation. The tensile strength of the weldments is found by testing in the Ultimate Tensile Strength (UTM) machine. The hardness test is performed by Vickers Hardness tester to characterize the welded area. Macro Vickers Hardness is performed in the welded area of the workpiece to finalize mechanical properties in different heat-affected zones of FSW welded workpiece to analyze and find the efficient input parameter of FSW. The efficient input parameter for TIG welding is identified and a comparative study is made and the result proves that FSW welding is a better welding technique.

Prediction of Optimum Welding parameters for Friction stir welding of Aluminium Alloy AA5083 Using Response Surface Method

Friction Stir Welding (FSW) is carried out on armour grade aluminium alloy AA 5083 with dimensions of 100X50X6.35 mm. The process parameters like tool profile play a significant role to enhance the welding. Many processing conditions influence the microstructure progression and mechanical behaviour of the produced joints. The main parameters involved in the welding process is discussed under this work. Various parameters such as welding speed, tilt angle, spindle speed and various tool profile are used. Analysing the mechanical behaviours of joints welded like tensile strength and hardness is investigated. In this work tool profiles are designed according to the specific dimensions and the tool material chosen is H13. The tool profiles which are chosen are Cylindrical, Tapered and Hexagonal. So, for this profile, the welds are made accordingly. The Study involves the process which is going to take place are Tensile strength, Impact strength, Hardness, and Microstructure. After the finished AA5083 welded aluminium alloy, it is cut in using the EDM machine according to the ASTM standard. The experiment is designed to determine the major factors affecting the hardness and tensile strength of the joints. For the speed of the tool, tool profile and forward movement of the tool tensile strength and hardness are studied. The contribution of each factor is determined from RSM; For the nine samples, the different factors which are used in this process are compared and investigated. These sample values are compared and analysed by using ANOVA. Based on the values obtained from the test the graph is plotted and based upon the speed of the tool from 1000 to 1500 rpm and forward motion of the tool from 18 to 24 mm/min values is investigated.

Surface Properties of Melts Based on Tin

This paper presents the results of the surface properties of the tin-based melts. It has been shown that the best wetting of Al-4 at. % Li grade aluminum, silicon, and piezoceramics are achieved by the eutectics and terectics of tin-aluminum, tin-zinc, and aluminum alloys, respectively. Preliminary photon annealing of the substrates for 3–4 sec improves the wetting of silicon and ceramics. Solder wetting is also improved by the addition of copper and nickel micro powders, alkaline, and alkaline earth elements.