Welding of a 7025 Al-Alloy by a Pulsed Mig Welding Process (original) (raw)
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International Journal of Engineering Research and Technology (IJERT), 2016
https://www.ijert.org/experimental-investigation-on-weldability-aspects-of-aluminium-6063-alloy-using-friction-stir-welding-and-gas-tungsten-arc-welding https://www.ijert.org/research/experimental-investigation-on-weldability-aspects-of-aluminium-6063-alloy-using-friction-stir-welding-and-gas-tungsten-arc-welding-IJERTV5IS040126.pdf In the present study aluminium 6063 plates were used to evaluate its weldability properties by using two different welding processes such as Friction stir welding (FSW) and Gas tungsten arc welding (GTAW). For both base metal and weld bead tensile properties and Vickers hardness values were evaluated as per ASTM standards. It is found that the ultimate tensile strength in both welding processes significantly decreased as compared to base metal. The Vickers hardness values of welded samples in both welding processes increased marginally. The above mechanical properties were correlated by using optical microscopy. Keywords-Aluminium 6063 alloy; tensile strength; Vickers hardness I. INTRODUCTION Aluminium alloys known to possess excellent corrosion resistance and significant lower density than other competing alloys of similar mechanical performance. To take advantage of these promising features in structural applications , methods of joining aluminium alloys must be thoroughly investigated and understand to maximize this structural capabilities of these aluminium alloys. Welding is a process of joining two similar or dissimilar metals (usually metals) through localized coalescence resulting from a suitable combination of temperature, pressure and metallurgical conditions [1]. Depending upon the combination of temperature and pressure, a wide range of welding processes, like-gas welding, arc welding, resistance welding, solid state welding, thermo-chemical welding and high energy beam welding, have been developed. All these welding processes result different weld bead profiles and angular distortions to weld-pieces as governed by the inherent characteristics of process and processing parameters. Al-Mg-Si alloys have been used extensively in the fabrication of aerospace, automotive and marine components due to their superior mechanical properties such as low density, high strength/weight ratio, excellent weldability [2]. Amongst Al alloys, Al-Mg-Si (6XXX) alloys have got further preference in industrial applications as these alloys contain very fewer amount of alloying elements (0.4 to 0.9 wt.% Mg and 0.2 to 0.6wt.% Si) which makes them cheaper than other series like AlCu (2XXX) and Al-Zn (7XXX) alloys [3]. Al alloys of the 6000 series
Effect of weld parameters on the properties of aluminium weldment
2006
Two different grades of aluminium pbtc> (lxxx and 5xxx ,.r1es) were welded \.ith two different filler metals (4043 and 5356) and with dIfferent current settmgs of 145A, 175/\ and 195A. Tung,ten Inert Gas ('1'10) welding process was used [or welding. Durmg weld"'g at dlffcrcnt conditions various eutectics, in!erme!allLc compounds and phases formed at dllTcrcm temperatures and at difTerent compositions. All of these phases contributed 10 a change Ln mechanical properties. In (he present research, a systematic mvcsllgMion was made on TIG welding of aluminium alloy to determine the probable reasons for evolutlon of ,olJdlli"allOn cracking of aiummmm weld and to improve the ,tructurepropel ty relalloosh,p "f wddmenl by controlling he"! input. It wa, expected that thc rcscar~h work will optlmL7.e (he process parameter to find out an 0pllmum condition for welding, When 4043 filler metal (Al-5% Si) was used for welding pure alummlum plate, (lxxx ,crie,) a ...
Introduction to Welding of Metallic Materials.: Methods, Metallurgy and Performance
Elsevier, 2023
Welding of Metallic Materials: Methods, Metallurgy and Performance looks at technical welding methods used based on different principles and sources, such as heat, with or without pressure, electrical, plasma, laser and cold-based welding. The metallurgical aspects associated with the welding processes, specifically those associated with metallic alloys, are explained, alongside the advantages and welding features that are associated with specific welding processes. In addition, the performance of metallic weldments under specific conditions and environments such as offshore, oil industry, radiation and high-temperature services are discussed. This book will a vital resource for researchers, practicing engineers and undergraduate and graduate students in the field of materials science and engineering.
Aluminum Alloy Welding in Automotive Industry
Transport Problems, 2020
The paper presents the possibilities of using light alloy components in vehicle construction. Material 6082 was chosen for use in responsible structural components. The structure and strength parameters of the material in the delivery state were tested. Tested material parameters were compared with normative requirements. The purpose of the paper is to check the mechanical properties of aluminum alloy welded joints by various processes and parameters. Until now, welding of 6082 alloy did not give good and repeatable results. Because of that, two welding methods were analyzed (MIG and TIG) in the field of the quality of welds, strength of welded joints, and material structures obtained as a result of welding with various parameters.
Effect of Heat Input on the Structure and Properties of Aluminium Weldment
Iranian Journal of Materials Science and Engineering, 2013
The probable reasons for evolution of weld porosity and solidification cracking and the structure- property relationship in aluminium welds were investigated. Aluminium plates (1xxx series) were welded by Tungsten Inert Gas (TIG) welding process, 5356 filler metal was used and heat input was controlled by varying welding current (145A, 175A and 195A). The welded samples were examined under optical and scanning electron microscopes and mechanical tests were performed to determine tensile and impact strengths. Secondary phase, identified as globules of Mg 2Al 3 precipitates, was found to be formed. Solidification cracking appeared in the heat affected zone (HAZ) and porosities were found at the weld portion. The tendency for the formation of solidification cracking and weld porosities decreased with increased welding current.
Modern use of metal alloys for the automotive industry
Metal and Casting of Ukraine, 2020
High strength aluminium alloy AA7075 (AleZneMgeCu) is a precipitate hardenable alloy widely used in the aerospace, defense, marine and automobile industries. Use of the heat treatable aluminium alloys in all these sectors is ever-increasing owing to their excellent strength-toweight ratio and reasonably good corrosion resistance. The shortage in corrosion resistance, however, usually poses negative concern about their reliability and lifetime when they service in the variable marine environments. These alloys also exhibit low weldability due to poor solidification microstructure, porosity in fusion zone and lose their mechanical properties when they are welded by fusion welding techniques. Friction stir welding (FSW) is a reliable technique to retain the properties of the alloy as the joining takes place in the solid state. The welds are susceptible to corrosion due to the microstructural changes in the weld nugget during FSW. In this work, the effect of post weld treatments, viz., peak aging (T6) and retrogression & reaging (RRA), on the microstructure, mechanical properties and pitting corrosion has been studied. Friction stir welding of 8 mm-thick AA7075 alloy was carried out. The microstructural changes of base metal and nugget zone of friction stir welds were studied using optical microscopy, scanning electron microscopy and transmission electron microscopy. Tensile and hardness test of base metal and welds has been carried out. Pitting corrosion resistance was determined through dynamic polarization test. It was observed that the hardness and strength of weld were observed to be comparatively high in peak aged (T6) condition but the welds showed poor corrosion resistance. The resistance to pitting corrosion was improved and the mechanical properties were maintained by RRA treatment. The resistance to pitting corrosion was improved in RRA condition with the minimum loss of weld strength.
Journal of Manufacturing and Materials Processing, 2018
This research work aims at finding the optimum process parameters for the laser welding of AA7020 aluminium alloys. The use of 7xxx series alloys is limited because of weldability problems, such as hot cracking, porosity, and softening of the fusion zone despite its higher specific strength-to-weight ratio. AA7020 aluminium alloy was welded while varying the process parameters so as to obtain optimal welding efficiency. The welded samples were analysed to reveal the microstructure, defects, and mechanical properties of the welded zone. The samples were prepared from a plate of AA7020, which was hot rolled at a temperature of 470 • C to a thickness of 1 mm. The welding was carried out at an overlap of 0.25 mm, duration of 14 ms and argon shield gas flow rate of 15 L/min. Process parameters, such as peak power, welding speed, and pulse shaping, were varied. The samples were welded with Al-5Ti-B and Al-5Mg as filler metals. The welding speed, peak power, and pulse shaping have a great influence on the weldability and hot cracking susceptibility of the aluminium alloy. Al-5Ti-B improves the microstructure and ultimate tensile strength of AA7020 aluminium alloy.
Effect of variable process parameter of MIG welding on aluminium alloy 6061-T6
The increasing use of aluminum alloys (6061-T6) in shipbuilding, aeronautics, marine frames, railway vehicles, bridges, offshore structure topsides, and automobile industry relevance due to its light weight and high strength to weight ratio. The present investigation is designed to study the effect of various process parameters (welding current, voltage, and angle of the torch.) in metal inert gas (MIG) welding processes on a bead on the plate of aluminum alloy 6061-T6. In this alloy, the weld fusion zone has coarse columnar grains because of the unequal he, at distribution during weld metal solidification. Electrode material has selected for MIa G welding as ER4043. Taguchi’s optimization technique and orthogonal array matrix were used to optimize and selection of the process parameters for better results.
A Comparison of Welding Techniques of Aluminium Alloys A Literature Review
Welding of aluminum alloys is an important issue because of their increasing applications in industries. The most widely used joining methods for aluminium alloys are Tungsten Inert Gas (TIG), Metal Inert Gas (MIG), Variable Polarity Plasma Arc (VPPA) and Friction stir welding (FSW). However, the high conductivity, high reflectivity, high reactivity and high coefficient of thermal expansion make welding of aluminium alloys difficult. In this paper, the research and progress of a variety of welding techniques for joining Al alloys are reviewed. The aim of the paper is to review the recent progress in the welding of aluminium alloys to provide a basis for follow-up research.
Characterisation of electron beam welded aluminium alloys
Science and Technology of Welding and Joining, 1999
2024 and 6061, were butt welded by autogenous electron beam (EB) welding. The fusion welding of alloy 5005 is not Electron beam (EB) welding was performed on three expected to present any major difficulty. The formation of diVerent aluminium alloys, namely alloys 2024, 5005, porosity may be the only concern in the welding of this and 6061 (plate thickness 5 mm except alloy 5005 alloy. On the other hand, the base metal mechanical which was 3 mm in thickness), to establish the local properties may be degraded in autogenous welding of alloys microstructure-property relationships that would 2024 and 6061. Furthermore, alloys 2024 and 6061 are both satisfy the service requirements for an electron beam crack sensitive alloys, and thus are more difficult to fusion welded aluminium alloy component with weld zone weld.1-4 However, the high thermal gradient from the weld strength undermatching. Microstructural characterinto the base metal in the low heat input EB process isation of the weld metals was carried out by optical creates very limited metallurgical modifications, and crack and scanning electron microscopy. A very low level sensitivity is therefore reduced. Owing to the low heat input, of porosity was observed in all EB welds owing the heat affected zone (HAZ) produced in EB welding is to surface cleaning before welding and the vacuum very narrow,5 and thus the problems associated with the environment of the EB welding process. Extensive HAZ are limited. However, as a result of the very high microhardness measurements were also conducted in temperatures experienced in the fusion zone, the loss of the weld regions of the joints. Global tensile properties some elements, for example vaporisation of magnesium, and f racture toughness properties (in terms of crack occurs during EB welding. The loss of such strengthening tip opening displacement, CT OD) of the EB joints were elements may degrade the mechanical properties of the determined at room temperature. T he eVects of strength welds by affecting the weld pool chemistry;6,8 also, in this mismatch and local microstructure on fracture case the strength of the fusion zone cannot be restored to toughness of the EB joints are discussed. T he purthat of the base metal by post-weld heat treatment. Several pose of the present paper is to report the partial researchers6,8-15 have reported the loss of alloying elements results of the European Brite-Euram project ASPOW in the welding of aluminium alloys. A common way of (assessment of quality of power beam weld joints; partially restoring the mechanical properties of the weld BRPR-CT 95-0021), which has been undertaken region is by the use of adequate filler alloy during welding. predominantly by industrial companies to establish The loss of strength in the fusion zone will cause a strain a European f ramework for destructive and nonconcentration in addition to the geometrical strain condestructive testing and assessment criteria for laser and centration that occurs if such a weld is exposed to an electron beam welds of over 20 metallic materials. external loading. Confined plasticity development within the undermatched EB weld zone will therefore reduce the Dr Ç am, Mr Ventzke, Dr Dos Santos, and Dr Koçak plastic straining capacity of the weld joint under tensile are at the GKSS Research Center, Institute of loading, as well as increasing the constraint within the Materials Research, Max-Planck-Strasse, D-21502 weld zone.16 An increase in constraint owing to confined Geesthacht, Germany, and Mr Jennequin and Mr plasticity may cause a reduction in the fracture toughness Gonthier-Maurin are with CNIM, Zone Industrielle of the sandwiched fusion zone, compared to an 'all fusion de Bregaillon, BP 208, F-83507 L a Seyne-Sur-Mer zone' compact tensile (CT) specimen. Of course, such an Cedex, France. Manuscript