Marine Grade Aluminium Research Articles

Friction Stir Welding between Marine Grade Aa 5083 and HSLA Steel

The revolutionary method of solid-state joining technique has already attracted significant attention of advance welding and joining research community. The technique has been continuously developing for many alloy systems for similar and dissimilar joints. Recent research in these areas aiming to join complex dissimilar alloy pairs, composite, polymers, ceramics etc. This paper presents a study of friction stir welding between marine-grade aluminum alloy AA 5083 and HSLA steel, configured in a butt arrangement. The study investigates the evolution of Fe-Al series of intermetallic layer formation at the joint interface and its effective management to yield best joint efficiency. The FSW in the said alloy pairs yielded an 83.25% welding efficiency based on the aluminum alloy side strength. XRD analysis along with SEM examination revealed the formation of Al13Fe4 and Al5Fe2 as intermetallic compounds which was confirmed by the EBSD analysis. The obtained results are discussed in the paper considering the effect of the weld joint performance.

Effect of TiB2 on the mechanical and tribological properties of marine grade Aluminum Alloy 5052: An experimental investigation

Aluminum Alloy 5052 is one of the excellent corrosion resistant alloys among the Aluminum 5000 series alloys. Despite the favourable corrosion resistance, it exhibits low resistance to wear and perform poorly in various tribological applications. This study attempts to investigate the impact of TiB2 reinforcement on the mechanical and tribological properties of Aluminum Alloy 5052 matrix alloy, fabricated using the stir casting technique. Composites with varying weight percentages (0, 2.5, 5 and 7.5 wt %) of TiB2 were prepared. Vicker's hardness testing was conducted to assess the effect of TiB2 content on composite hardness. Hardness of composites increased from 65.5 to 85.16 HV in tandem with the TiB2 content depicting a rise of about 30 %. Tribological properties were studied through dry sliding wear tests using a pin-on-disc tribometer, with varying loads (10 N and 50 N) and sliding speeds (1 m/s and 3 m/s). The results demonstrate that the addition of TiB2 significantly improves the wear resistance of the composites, being optimum in composite with 5 wt % of TiB2. A maximum increase of about 36 % in wear resistance was observed at high load and high-speed conditions corresponding to 5 wt % TiB2 concentration. FESEM analysis revealed distinct wear modes and the role of TiB2 in changing the wear mechanism from abrasion to delamination. This study underscores the pivotal role of TiB2 in enhancing the mechanical and tribological properties of Aluminum Alloy 5052, expanding its application scope, particularly in lightweight engineering applicationsin general and marine in particular.

Underwater friction stir welding of marine grade aluminium alloys: A review

Aluminium alloys of the 5xxx and 6xxx types are considered marine grade alloys. These alloys are highly resistant to corrosive environments and are therefore used in maritime applications. However, joining these alloys by traditional welding process is a difficult task and can also lead to defect formations in the joints. Friction stir welding being a solid-state welding process uses a special type of tool to join workpieces at a temperature below the melting point of the material. This process saves a lot of energy, is eco-friendly and also yields better mechanical properties than the conventional fusion welding processes. However there is a decrease in the mechanical properties of the joints since the heat cycles involved in FSW can lead to softening of the joints. Underwater friction stir welding is a modification of FSW where welding is performed under the influence of a liquid medium like water. UFSW reduces the peak temperature of welding and produces better mechanical properties than the normal FSW process. A review of underwater friction stir welding of marine grade aluminium alloys is provided here. A review regarding the different parameters of the process, microstructure development, and corrosion resistance is discussed in this paper. From the review, it can be inferred that UFSW is very effective for joining marine grade aluminium alloys with minimal defects and better mechanical properties.

Numerical Modeling for Prediction of Surface Morphology and Volumetric Defect Using Coupled Eulerian–Lagrangian Approach during Friction Stir Welding of Marine Grade Aluminum Alloy

Numerical Modeling for Prediction of Surface Morphology and Volumetric Defect Using Coupled Eulerian–Lagrangian Approach during Friction Stir Welding of Marine Grade Aluminum Alloy

Selective alloying of pure aluminum with varying amounts of magnesium using friction stir processing for improved mechanical and corrosion-resistant properties

This study investigates the effects of adding different amounts of Mg to the surface of pure Al substrate using friction stir processing (FSP) technique to prepare Al–Mg solid solutions. For this purpose, machined grooves on the surface of the pure Al plates were filled by bulk Mg blocks and FSPed to form Al–Mg solid solution layers with ∼2.0, 4.5, and 33.9 at.% Mg. The chemical composition, microstructure, and surface Volta potential of the surface alloyed layers were studied by SEM/EDS, XRD, and SKPFM, respectively. The results revealed that incorporating Mg into the Al substrate causes a considerable refinement of the microstructure, resulting in a significant increase in Vickers hardness number from 25 to 208.4 HV (∼734% increase). As the Mg content in the alloyed layer increased, a transition from a single-phase solid solution structure to a dual-phase structure was observed. Based on the potentiodynamic polarization results, it is evident that the corrosion resistance of the single-phase alloyed layer can match that of marine-grade aluminum alloys.

Thermomechanical and Material Flow Analysis during Friction Stir Welding of Marine Grade Aluminum Alloy 5083

_ This research aims to depict the thermal history, residual stress distribution, axial force applied, and material flow behavior on aluminum alloy 5083 (AA5083) plates, during the friction stir welding (FSW) process. This alloy finds most its use in shipbuilding industries and for marine constructions. It has been developed using an explicit, fully coupled thermomechanical nonlinear finite element (FE) analysis approach. The analysis was performed to simulate the effect of three stages, namely plunging, dwelling, and welding, of the FSW process. The ABAQUS/Explicit program was used for the computational modeling. To build a reliable and computationally efficient FE model, features such as arbitrary Lagrangian-Eulerian (ALE) formulation, adaptive meshing/ remeshing approach, mesh sensitivity analysis, and mass scaling have been introduced. The interaction between the tool bottom surface and the plate top surface was defined using a finite sliding and a sticking property. A Coulomb friction model with a temperature-dependent coefficient of friction (COF) was used to describe the tool-workpiece interaction. In addition, a small experiment was done with the following process parameters; a rotating tool speed of 875 rpm, a traverse speed of 60 mm/min, and a tool tilt angle of 0° to produce a defect-free butt joint to validate the numerically generated thermal profiles. The temperature was found slightly higher on the advancing side (AS). Residual stress distribution created over the whole width of the plates was also investigated. Introduction The introduction of friction stir welding (FSW) process by The Welding Institute in 1991 (Thomas 1991) drew much attention. During fusion welding of 5 mm AA5083 plates, the heat input should be very high. Because of this high input, a higher thermal gradient is produced, which leads to the formation of several intermetallic compounds (IMCs). Because of this IMC formation, the strength of the welded joint is reduced. However, the steep thermal gradient produced leads to the formation of finer microstructure near the weld bead and coarser along the base metal region. These results in the heterogeneity of the weld bead microstructure leading to less efficiency and accuracy of the weldment.

Metal Matrix Composite Fabricated with 5000 Series Marine Grades of Aluminium Using FSP Technique: State of the Art Review

Aluminium metal matrix composites have been shown to make significant contributions to the area of new materials and have become widely accepted in high-tech structural and functional applications such as those in the aircraft, automobile, marine, mineral, defence, transportation, thermal management, automotive, and sports and recreation fields. Metal matrix composites are manufactured using a variety of manufacturing processes. Stirring casting, powder metallurgy, squeezing casting, in situ processes, deposition techniques, and electroplating are part of the manufacturing process used in the manufacture of aluminium-metal matrix composites. Metal matrix composites that use friction stir processing have a distinct advantage over metal matrix composites that use other manufacturing techniques. FSP’s benefits include a finer grain, processing zone homogeneity, densification, and the homogenization of aluminium alloy and composite precipitates. Most metal matrix composite investigations achieve aluminium-metal matrix composite precipitate grain refinement, treated zone homogeneity, densification, and homogenization. This part of the work examines the impact of reinforcing particles, process parameters, multiple passes, and active cooling on mechanical properties during the fabrication of 5000-series aluminium-metal matrix composites using friction stir processing. This paper reports on the available literature on aluminium metal matrix composites fabricated with 5xxx series marine grade aluminium alloy using FSP.

Metallographic analysis of in-house developed marine grade aluminum alloy AA5086friction stir welds

A friction stir welding (FSW) setup was developed and performed trial experiment on marine grade aluminum alloy 5086 in the present work. The input parameters were traverse speed (56 and 80 mm/min) and spindle speed (750 and 1000 rpm). From study it was observed that the spindle speed has an immense influenced on joint formation compared to feed speed. The rotational speed of 750 rpm produced defect joints due to inadequate welding heat generation and joints without defect were achieved at 1000 rpm spindle speed. The metallographic analysis and mechanical testing were conducted for the defect-free weld joints.

Finite element simulation of liquid nitrogen temperature rolling of marine grade aluminium alloy 5754

Now days, numerical approaches are becoming an efficient practical tool for the analysis of elastoplastic behavior of various engineering materials. Present study elaborates about the numerical investigation of liquid nitrogen temperature (LNT) plate rolling operation of marine grade aluminium alloy 5754 (AA 5754) by finite element method. To serve this purpose, commercially available ANSYS software package has been utilized to perform LNT-rolling simulation. In literature, it is well documented that LNT-rolling immensely increases mechanical strength through grain refinement technique. During rolling at liquid nitrogen temperature, the dynamic recovery process is inhibited which leads in accumulation of high rate of dislocation defects. Consequently, with due rolling these accumulated dislocations attributed towards formation of ultrafine grain (UFG) structure. The aim of this work is to formulate an efficient method to numerically investigate the deformation characteristics of AA 5754 during LNT-rolling. Geometrical and experimental parameters like roller diameters, dimensions of flat plate, roller speed, friction coefficient etc. are incorporated in the preprocessor module of ANSYS software. An optimized meshed domain is selected for simulation of 40% thickness reduction of AA 5754. The temperature effect and corresponding stress distribution in the flat plate of AA 5754 is well captured and comparative analysis with the experimental practices has been successfully carried out. Numerical results obtained in the form of uniform thickness reduction, elastoplastic stress and strain contour plots, pressure force exerted by roller etc. are in good agreement with the experimental rolling operation.

Process - Property Correlation of Friction Stir Welding of Marine Grade Aluminium Alloy 5083 Using Finite Element Analysis

In this article, a 3D finite element based thermo-mechanical model for friction stir welding (FSW) of a marine-grade aluminium alloy 5083 is proposed. The model demonstrates the thermal evaluation and the distribution of residual stresses and strains under the variation of process variables. The temperature profile of the weld joint during the FSW process and the mechanical properties of the joints are also experimentally evaluated. The necessary calibration of the model for the correct implementation of the thermal loading, mechanical loading, and boundary conditions was performed using the experimental results. The model simulation and experimental results are analyses in view of the process-property correlation study. The residual stress was evaluated along, and across the weld, centreline referred as longitudinal and transverse residual stresses, respectively. The magnitude of longitudinal residual stress is noted 60-80% higher than that of the transverse direction. The longitudinal residual stress generated a tensile oval shaped stress region around the tool shoulder confined to a maximum distance of about 25mm from the axis of the tool along the weld line. It encompasses the weld-nugget to thermo-mechanically affected zone (TMAZ), while the parent metal region is mostly experiences the compressive residual stresses. However, the transverse residual stress region appears like wing shaped region spread out in both the advancing and retreating side of the weld and occupying approximately double the area as compared to the longitudinal residual stresses. Overall, the study revealed a corelation between the FSW process variables such as welding speed and the tool rotational speed with the residual stress and the mechanical properties of the joint.

Optimization of process parameters of friction stir welded joints of marine grade AA 5083

Abstract Friction Stir Welding is an innovative solid-state joining technique commonly utilized in industries. It is a combination of highly multifaceted process utilizing several coupled mechanisms. Although, large number of researchers are working in this field to reveal the maturity of the process evolving many plausible application and materials. Still the process needs intensive study to optimize production procedures that will yield high quality stronger welds from the stirring action of the tool and pin into the weld plate material. In this part of the research the study to know the influence process parameters and tool pin geometry on friction stir welding (FSW) of marine grade aluminium (5083) especially in reference to microstructure and mechanical properties of weld has been highlighted so as to optimize the welding parameters along with the tool geometry. Tensile properties of the joints have been studied and their correlations with the process parameters along with the tool parameters have been investigated. The highest joint efficiency of 75.67% efficiency with the ultimate tensile strength (UTS) of 212 MPa was noted in the case of FSW joint fabricated by T1 tool with 1000 rotational speed and 28 mm per minute of welding speed. Also, microstructures of various zones of FSW sample have been evolved and correlated with the process parameters which explains the dynamic recrystallization process at the nugget zone of FSW joint.

Corrosion and fouling study of copper-based antifouling coatings on 5083 aluminum alloy

Potentiostatic and electrochemical impedance spectroscopy (EIS) were used to evaluate cuprous oxide (Cu2O) containing coating systems on the localized corrosion of 5083 marine-grade aluminum in simulated ocean water. Test panels coated with a complete coating system and flawed to simulate a coating defect were also exposed for a 3-month field immersion to evaluate differences between Cu2O and cuprous thiocyanate (CuSCN) pigments on fouling and corrosion behaviour. Optical microscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) were used to evaluate deposits formed on the surfaces after exposure. Results imply that copper leaching from the Cu2O pigment can deposit on the surface marine-grade aluminum, with or without cathodic protection. Cathodic protection resulted in the formation of protective calcareous deposits at potentials more electronegative than −1000 mV versus silver-silver chloride (Ag/AgCl). Cuprous oxide was shown to be a more resistant to biofouling than the cuprous thiocyanate, but there was an increased likelihood of coating delamination and localized corrosion with the former antifouling pigment.

An Artificial Intelligence Based Approach to Determine the Elongation % and Ultimate Tensile Strength of Friction Stir Welded Dissimilar Marine Grade Aluminium Alloy Joints

Neural networks are a new generation of information processingparadigms designed to mimic some of the behaviours of the humanbrain. These networks have gained tremendous popularity due to theirability to learn, recall and generalize from training data. A number ofneural network paradigms have been reported in the last four decades,and in the last decade the neural networks have been refined and widelyused by researchers and application engineers. This study focuses on theprediction of the elongation % and Ultimate Tensile Strength (UTS) ofthe dissimilar Friction Stir Welded joints of aluminium alloys by trainingthe Neural Network on Quasi Newton Algorithm.How to cite this article:Mishra A, Singh A, Saravanan M et al. An ArtificialIntelligence based Approach to Determine theElongation % and Ultimate Tensile Strength ofFriction Stir Welded Dissimilar Marine GradeAluminium Alloy Joints. J Adv Res Appl Arti IntelNeural Netw 2019; 3(1): 1-21.

The effects of welding speed on the microstructure and mechanical properties of marine-grade aluminium (AA5754) alloy welded using MIG welding

The effects of welding speed on the microstructure and mechanical properties of marine-grade aluminium (AA5754) alloy welded using MIG welding

Numerical Investigation of the Adhesive Damage Used for the Repair of A5083 H11 Aluminum Structures by Composites Patches

In addition of binding the patch to the cracked material, adhesives play an important role in bonded composite repair because they make the bridge of transfer of loads between the patch and the cracked material. Indeed, any damage in adhesives will affect the efficiency and the performance of the repaired structure by composite patches.In this paper, two different adhesive shapes were numerically investigated, using finite element method in order to estimate the damage zone area on the adhesive bonded composite repair in 5083 marine grade aluminum alloy and its effect on the efficiency and performance of the repaired structure. The obtained results proved that the circular shape causes less damage than the rectangular one for the three crack lengths chosen. Moreover, both shapes of adhesive maintain their performance repair without disband risk and without reaching the critical value defined by Ban and co-authors (Dr=0.2474). Furthermore, it is concluded that the damage zone increases with the increase of the adhesive thickness and the decrease of the patch thickness and the use of circular shape is more effective than the rectangular one for the configurations and loading conditions studied.

Investigation of fatigue and fracture behaviour of sensitized marine grade aluminium alloy AA 5754

AbstractIn the present study, fatigue and fracture characteristics of sensitized marine grade Al‐Mg (AA 5754) alloy are experimentally evaluated. Received alloy is sensitized at temperatures of 150°C (SENS50) and 175°C (SENS75) for 100 hours. Fracture parameters, KIc and JIc, are experimentally evaluated. Slow strain rate tensile tests at a crosshead speed of 0.004, 0.006, and 0.01 mm/min; fatigue crack growth tests at load ratios (R = Pmin/Pmax) of 0.1, 0.2, and 0.5; and low cycle fatigue tests at four strain amplitudes of (0.3‐0.6)% are performed for SENS50 and SENS75 alloys. Relatively lower magnitude of fracture toughness values are observed for SENS75 specimen. Severe degradation in tensile properties, fatigue crack growth characteristics, and low cycle fatigue lives are observed for SENS75 samples. Extended finite element method is adopted to simulate the elasto‐plastic crack growth during fracture toughness evaluation. Scanning electron microscopy (SEM) is used to understand the failure mechanism of sensitized alloys.

Parametric optimization of friction stir welding process for marine grade aluminum alloy

Purpose The purpose of this paper is to deal with the experimental data related to the friction stir welding (FSW) of marine grade Al-Mg4.2 alloy. Mathematical models are developed to study the individual and interaction effects of input variables on the performance characteristics of joints. FSW parameters are optimized to maximize the yield strength and weld nugget microhardness of the welded joints. Design/methodology/approach Response surface methodology is applied to establish the mathematical relationship between six input factors, namely, tool rotational speed, transverse speed, tool shoulder diameter, tool material hardness, tilt angle and pin profile; and two response variables, namely, yield strength and weld nugget microhardness. Six factors–five-level rotatable central composite matrix is used for the design of experiments. The quadratic model is used, as suggested by the design expert software, to express the response parameters as a function of investigated input parameters. The competence of the developed models is verified through analysis of variance. Findings The present investigation clearly indicates that the studied input factors have a significant effect on the quality of the joints. The optimal combination of input factors is determined to achieve the desired responses. Originality/value This paper teems a new look on tensile and hardness properties of Al-Mg4.2 joints by relating the microstructure, fractrographs and grains distribution with the dynamic recrystallization and plasticized material movement during the FSW process. The outcome of this research will help in seizing the opportunities of joining Al-Mg4.2 alloy using FSW, in the offshore and marine applications.

Effect of Welding on Pitting and Intergranular Corrosion Behavior of Marine Grade Aluminum Alloy

AA 5052 H32 aluminum alloy is one of the most commonly used materials in the marine environment due to its good formability, good weldability, and better corrosion resistance. Assessment of resistance of welds of the alloy against corrosion is necessary for reliable design. In the present study, pitting and intergranular corrosion behavior of tungsten inert gas (TIG), normal friction stir welding (FSW), and underwater FSW (UFSW) joints of AA 5052 H32 aluminum alloy and parent alloy are investigated. Electrochemical corrosion behavior by Tafel polarization technique and intergranular corrosion susceptibility by mass loss of the specimen in concentrated nitric acid solution are studied as per ASTM standards. The corrosion studies were conducted on welded plates for which welding parameters during TIG welding and FSW were kept optimum for maximum tensile strength. The result shows that corrosion resistance of welded joints is inferior to that of parent metals. Corrosion resistance of the FSW joint and UFSW joint are nearly equal and found to be higher compared with the TIG joint. Density and size of pits formed on the parent metal and welded joints are examined via macro- and microscopic analysis and atomic force microscopic study. Results also show that the specimens welded by FSW and UFSW processes are immune to intergranular corrosion attack.

Microstructural influence on damping for Friction stir welded Aluminum plates

Friction Stir Welding (FSW) is a solid state welding process. in which a rotating tool moves along the butted surfaces of rigidly clamped plates to form the weld. The speed of rotation, the axial load, feed rate and the type of tool influences the structural properties of the weld. An experimental study was carried out on Marine grade aluminum plates by varying the carriage speed, rotor speed and tools. A parametric study was carried out using three sets of carriage speed, rotor speed and tools. Further the FSW welded plates were analyzed for strength using universal testing machine. From the test results best, intermediate and worst cases were separated out based on the tensile strength and strain. One of the contributing factors towards this variability could be the sensitivity of friction coefficient. This results in improper heating and material distribution across advancing and retreating side. The microstructure of the welds was analyzed using. Next the influence of these microstructural grain properties on macroscopic damping behavior was analyzed by carrying out a modal testing on the welded structure. Understanding the damping behavior is helpful in characterizing the vibration of the structure. Sensitivity analyses on the variations in the damping for different natural frequencies were carried out. The study clearly indicated a sensitivity of damping on the microstructural properties the FSW welded plates.

Investigations on friction stir welding of AA5083-H32 marine grade aluminium alloy by the effect of varying the process parameters

Friction stir welding is a new technique for the complicated task for welding the aluminum alloys. The experimental work presents a complete study on friction stir welding of armour grade aluminium alloy. The input process parameters producing effects were completely analysed. The basic principles of FSW are illustrated; including thermal history and material flow before discussing how the process parameters affect the weld microstructure and related distribution of hardness are examined for AA5083-H32.The Aluminium alloys such as H5083 called armour grade. Aluminium alloy 5083 exhibits the tremendous performance in the extreme environments. The material mostly applied in construction of ship building, vehicle bodies, mine skip and cages and pressure vessels. The effect of input parameters such as tool profile, rotational speed, and translational speed was investigated. The thermal histories, micro hardness and tensile strength were analysed. Dynamic polarization test was performed for measuring the pitting corrosion resistance. The parameters ranges from 700 to 1400rpm and feed rates from 20 to40 mm/min.The optimized input values which produced good tensile and harness values.