Combination Of Welding Parameters Research Articles

Ultrasound-assisted facile synthesis of a new tantalum(V) metal-organic framework nanostructure: Design, characterization, systematic study, and CO2 adsorption performance

This work presents a fast route for the preparation of a new Ta(V) metal-organic framework nanostructure with high surface area, significant porosity, and small size distribution. X-ray diffraction (XRD), scanning electron microscopy (SEM), Transition electron microscopy (TEM), energy dispersive spectrometer (EDS), thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), CHNS/O elemental analyser, and Brunauer-Emmett-Teller (BET) surface area analysis were applied to characterize the synthesized product. Moreover, the influences of ultrasonic irradiation including temperature, time, and power on different features of the final products were systematically studied using 2k-1 factorial design experiments, and the response surface optimization was used for determining the best welding parameter combination. The results obtained from analyses of variances showed that ultrasonic parameters affected the size distribution, thermal behaviour, and surface area of Ta-MOF samples. Based on response surface methodology, Ta-MOF could be obtained with mean diameter of 55nm, thermal stability of 228°C, and high surface area of 2100m2/g. The results revealed that the synthesized products could be utilized in various applications such as a novel candidate for CO2 adsorption.

Parametric Optimization of Gas metal arc welding process by PCA-based Taguchi method on Ferritic stainless steel AISI409

In the present work AISI 409 ferritic stainless steel samples have been welded by MIG welding. Butt joints have been made. Plate thickness is kept constant (= 3mm). Some important parameters have been varied during welding. Thus several butt-welded joints have been made. Each sample of the joints has been prepared under certain combination of welding parameters. The parameters considered for variation, in the present work have been welding current, gas flow rate and nozzle to plate distance. The design of experiment has been done using L9 Taguchi design of experiment. The influence of the process parameters (mainly current, gas flow rate and nozzle to plate distance) has been examined visually and also through X-ray radiographic tests. Next, samples have been cut, machined to conform to some specified dimensions for tensile testing. The quality of the weld has been evaluated in terms of ultimate strength, yield strength and percentage of elongation of the welded specimens. The observed data have been interpreted, discussed and analyzed by using principal component analyses (PCA). Optimum parametric setting has been predicted and validated as well. Useful interpretations of the experimental results and subsequent analysis have been made to draw some meaningful conclusions.

Multi-performance optimization of small-scale resistance spot welding process parameters for joining of Ti-1Al-1Mn thin foils using hybrid approach

The progressive trends of product miniaturization and light-weighting necessitate the effective microjoining of ultra-thin metal foils with high reliability and performance. In this experimental investigation, Ti-1Al-1Mn foils of 0.05 mm thickness were welded by small-scale resistance spot welding (SSRSW). The experiments based on Taguchi L27 orthogonal array have been implemented to examine the effects, significances and optimal combination of welding parameters, namely welding current, electrode force, ramping time and welding time. Performance measures viz., tensile-shear force, peel force, variances of tensile-shear and peel force were optimized by a hybrid approach comprising gray relational analysis (GRA) with principal component analysis (PCA). Furthermore, two kinds of weighted gray relational grade which extracted different numbers of principal components were put into comparison for better comprehensive performance by analysis of variance (ANOVA) and confirmation tests. It indicated that the procedure of parameter optimization should only extract all the principal components that correspond to eigenvalues larger than one. The ANOVA results showed that welding current was the most significant impact on multi-performance, followed by electrode force and ramp time, while welding time showed little effect. Finally, the optimal welding parameters combination was at welding current of 800 A, electrode force of 35.6 N, ramp time of 5 ms, and welding time of 8 ms.

Effects of FSW parameters and pin geometry on the weldability of EN AW 2024 alloy

Abstract Fusion welding techniques are not recommended for the welding of EN AW 2024 aluminum alloy due to its dendritic structure, porosity, slug inclusion and distortion, etc. To prevent a decrease in weld joint strength, solid state welding techniques represent a more suitable alternative. Friction stir welding is commonly used for welding of aluminum alloys due to the welding temperature which is below melting point. The aim of the present study is to determine the optimal friction stir welding parameters using Taguchi-based Grey relational analysis. The tool pin shape, tool rotational speed and welding speed were considered as process parameters, while the ultimate tensile strength and percentage of elongation were considered as performance characteristics. The optimal level of each welding parameter was determined by the highest mean Grey relational grade of each parameter. The predicted optimal welding condition was confirmed by experiments. The effect of each parameter on the Grey relational grade was investigated using the probability value and the percentage contribution obtained from the analysis of variance. The results of the Grey relational analysis showed that the optimal friction stir welding parameter combination was the pin shape at first level with tool rotational speed of 500 rpm and welding speed of 80 mm × min−1 (PS1TRS1WS2). The evaluation of analysis of variance results indicated that the parameter with the highest contribution to the Grey relational grade value was the tool rotational speed, 39.79 %, and also, it has a large effect, at a 90 % significance level. An investigation of the macrostructure of each welded joint exhibited a sound weld joint for the triangular shaped pin. The tool rotational speed of 800 and 1000 rpm produced the lowest quality in welded joints due to a range of defects in the nugget zone.

Prediction and optimization of weld bead geometry for electron beam welding of AISI 304 stainless steel

Electron beam welding, though considered a sophisticated welding process, still requires the operator to first carry out several trial welds to find the right combination of welding parameters based on intuition and experience. This archaic method is often unreliable, leading to unproductive manufacturing lead time, man hours, quality control tests, and material wastage. The current study eliminates this “trial and error” method by providing a reliable model which can predict the right combination of weld parameters to achieve a high-quality weld. Beads on plate welds were carried out on AISI 304 stainless steel plates using a low-kilovolt electron beam welding (EBW) machine. A model that can predict weld bead geometry and provide optimized output for minimum weld area condition without compromising on weld quality was developed. Experimental data were collected as per full factorial design of experiments, and the levels for each input parameter were established through pilot experiments. A multivariate regression analysis has been conducted to establish a relationship between four weld input parameters (three levels each) and four weld bead responses. Response surface methodology (RSM) has been used to study the interrelationship between input parameters and their effect on each response variable. Further, minimization of weld cross-sectional area was done using genetic algorithm for maximum penetration and minimum weld area condition. The optimized mathematical model convincingly establishes that the focusing current is a significant input parameter with very high influence over the weld bead geometry. Extensive material characterization and mechanical tests have been carried out to validate the regressed input-output relationship and the optimized mathematical model.

Metallurgical response of weld metal to different filler metal and joint design combinations of laser-arc hybrid welded lean duplex and novel ferritic stainless steels

Laser and laser-arc hybrid welding of duplex and ferritic stainless steels is demanding, because microstructure of the welds tends to be highly ferritic. Therefore, filler metal must be used for maintaining corrosion and mechanical properties of the welds. In this study, different filler metals including duplex, basic, and overalloyed austenitic grades were used with laser-arc hybrid method to weld lean duplex 1.4162 and novel ferritic stainless steels grades 1.4622 and 1.4509. Several sets of joint design and welding parameter combinations were used to adjust the amount of filler metal in the weld. The purpose of the trials was to evaluate whether weld metal microstructures (grain morphology, austenite/ferrite balance, etc.) can be modified by using an applicable joint preparation and an “overmatched” filler metal addition. Weld characterization included several research methods such as: Macro- and microscopic examination using light microscope¸ cross-sectional dilution ratio determination from the metallographic cross sections, electron backscatter diffraction method in order to assess austenite, and ferrite phase proportions in the test welds. The effects of used groove geometry, filler metal composition, and content on resulting metallurgical features of the welds are discussed in detail.

Multiple Quality Characteristics Prediction and Parameter Optimization in Small-Scale Resistance Spot Welding

This study focuses on prediction and optimization of multiple quality characteristics in small-scale resistance spot welding of titanium alloy. Grey relational analysis was first conducted to roughly estimate the optimum welding parameters combination. Multiple regression analysis was then implemented for a local parameter optimization. Optimum welding parameters were determined by desirability function and multi-objective genetic algorithm approach separately. A back propagation neural network model was also performed to simulate relationship between welding parameters and single output of the first principal component. Performance of the particle swarm optimization was better than genetic algorithm in obtaining optimum welding parameters. The neural network-based model was very effective in global optimization. A good agreement could be found between experimental results and predicted weld quality characteristics. Weld quality could be found significantly improved with the proposed methods.

Influences of TIG welding parameters on tensile and impact behaviour of aluminium alloy joints: A Review

Aluminium is a non-magnetic, silvery-white, ductile and soft metal which is the most abundant metal and the third most abundant element in the earth crust. It also makes its existence in the form of its alloys in which aluminium is predominant metal. Copper, magnesium, manganese, silicon, tin and zinc are the typical alloying metals. Aluminium alloys are widely used in engineering structure, components and aerospace manufacturing where light weight and corrosion resistance is required. TIG welding is a precise and fastest welding technique able to weld ferrous and non-ferrous metals. It is highly controllable, fumeless and spatter less clean process needs very little finishing or sometime no finishing. The present work deals with the identification of best combination of welding parameters for TIG welding of AA7005. From the literature survey, it is found that welding of aluminium is very difficult with conventional arc welding processes. There are no. of welding parameters which affect the welding quality for again repeatability. Different parameteric ranges & their effects are studied. In this particular study, TIG welding set up will be used to weld 10mm thick AA7005 plate by changing the welding parameters. The effect of these parameters on tensile and impact strength of welding joints will be analyzed. KeywordsTIG welding, AA7005, Welding current, Gas flow rate, Welding speed, Tensile strength, Impact strength.

Study of Welding Parameters Effect on the Weld Quality for Structural Steel S235 J0

Welding technology at current level provides wide range of applications such as automotive or aerospace industries. New technique, ways of approach and use of new materials (for example aluminum or composite parts of car body parts) creates necessity of optimizing of welding.The article is focused on welding of two parts using Metal Active Gas (MAG) welding. The main task is to design most suitable parameters for welding structural steel S235 J0. Samples were prepared by CNC machining center by chamfering edges 30°. Machined samples were placed against each other creating angle of total 60°. Welding machine Einhell BT-GW 170 MAG was used to create V and Y shaped welds with various technological parameters. Goal of the article is experimentally determine combination of technological parameters for V and Y shaped weld joints of steel components with thickness of 6 mm focused on hardness. Every welding machine and of course additive material has some recommended values of parameters in large scale, therefore it is necessary to determine most appropriate combination of main welding parameters. Data obtained from experiment showed most suitable combination of variables of welding process in order to achieve highest quality of weld joint.

Optimization of Friction Welding in Dissimilar Materials through Taguchi Based Grey Relational Analysis

Friction welding is widely used in determining the mass production process for joining dissimilar materials due to its environment friendliness, production efficiency and low heat input. In this study, Taguchi approach was applied in grey relational analysis to solve the multi-response optimization. The experimental result analysis is to achieve the maximization of tensile strength and minimization of weld time and metal loss. The optimal combinations of welding parameters are predicted through grey relational analysis for the multi-performance and optimal results were verified through confirmation test.

The use of hot air welding technologies for manufacturing e-textile trasmission lines

This study investigated the potential possibilities for obtaining textile transmission lines by incorporating conductive yarns into fabrics through a hot air welding process. Hot air sealing for obtaining textile transmission line was conducted using 100 % PES woven fabric, GoreTex® waterproof welding tape and seven different conductive yarn types, in order to form different textile transmission lines. By manufacturing using a hot air seam-sealing machine different welding parameters like welding temperature, pressure and velocity were chosen in order to find an optimal welding process for the selected fabric samples. The effects of welding parameters were examined on the electrical properties of the textile transmission lines in terms of conductivity and signal-transferring capability. Besides, the bending properties and morphologies of the welded textile transmission lines were also characterized and subjective evaluations of the appearances of textile transmission lines like puckering and the visual appearances of the surface sides of the welded textile transmission lines. The results based on conductivity and signal transferring capabilities were really promising for the manufacturing of etextile transmission lines via hot air welding technology. Moreover, the results based on bending properties showed that the lower the welding parameters the less rigid the hot air welded textile transmission lines became after welding all the used conductive yarns. Further, suitable combinations of welding parameters with the used components of textile transmission assured suitable visual appearances of the welded textile transmission lines. In this respect this research work offers a usage for hot air welding technology regarding the formations of textile transmission lines which are reliable and durable in functionality while still preserving the textiles’ aspects.

Empirical Modeling and Multi-Response Optimization of Laser Transmission Welding of Polycarbonate to ABS

In present research, laser transmission welding of polycarbonate to ABS has been investigated through empirical modeling. The effect of laser power, welding speed, stand-off distance and clamp pressure on weld strength and track width is investigated using the empirical models developed by response surface methodology. Laser power and stand-off distance have shown the dominant effect on the weld strength and track width, respectively. Numerical and graphical optimization schemes are used to find out the optimal welding conditions which satisfy multiple objectives, simultaneously. The optimal welding parameter combinations are presented in favors of high welding strength and low track width. Overlay graphs are plotted by superimposing the contours for the various response surfaces. Optimal solutions are found that would improve the weld quality within the selected range of process parameters.

Tensile Strength and Hardness Correlations with Microscopy in Friction welded Aluminium to Copper

Aluminium and copper are good conductors of heat and electricity, copper being the better conductor, is a costly metal indeed. On the other hand, aluminium is cheap, easily available and also has a lower density than copper. Hence, worldwide efforts are being made to partially replace copper wire. Solid state welding should be used to join aluminium to copper. This is because the use of fusion welding results in brittle phases formed in the weld interface. One of the solid state welding techniques used for joining aluminium to copper is friction welding. In this paper, an attempt has been made to join aluminium to copper by friction welding by varying the friction welding parameters, namely friction pressure, upset pressure, burn-off length and speed of rotation of the workpiece. Nine different friction welding parameter combinations were used during welding in accordance with ASTM standards and results have been reported. Tensile strength and hardness tests were carried out for each parameter combination. Optimum friction welding parameter combination was identified with respect to tensile strength. Scanning Electron Microscopy and Electron dispersive spectroanalysis were obtained to identify modes of fracture and presence of intermetallic phases for each friction welding combination with the aim to narrow down friction welding parameters that give good properties on the whole.

Microstructural and Mechanical Observations of Galvanized TRIP Steel after Friction Stir Spot Welding

Friction stir spot welding was done in transformation-induced plasticity steel sheets coated with zinc. The influence of tool rotational speed and dwell time on the microstructure and mechanical properties of lap-joints were investigated. After processing, different zones were formed in the joints. Microstructures in each zone depended on the welding conditions employed. Higher dwell time coupled with higher rotational speed promoted the deposition of a large amount of allotriomorphic ferrite beside the keyhole left by the pin. Coalesced bainite formation was stimulated by the deformation. Mechanical and chemical stabilization of the austenite occurred in different welding zones. Some zinc from the coating remained in the joint, in the stirring zone, representing a partial bonding between the steel sheets. The strength of the welds depended on a complex interaction between geometrical features, such as bonding ligament length and distance between the zinc and the keyhole left by the pin and the resultant microstructure in the stirring zone. The highest joint strength was observed for the “lowest tool rotational speed–highest dwell time” combination of welding parameters.

Optimization of strength of friction stir welded joints for AISI 430 ferritic stainless steels by genetic algorithm

In this paper, friction stir welding technique was used to join ferritic stainless steels, AISI 430. Ferritic stainless steel sheets were successfully joined considering both, the appearance of the welding bead and the strength of the welded joint by selecting proper weld parameters and tool material. The weld parameters such as revolutions, traverse speeds, compressive tool forces and tool tilt angles influenced the tensile strength of welded joints. Genetic algorithm model was developed to perceive the stronger joints by selecting proper welding parameter combinations. The strong welded joint higher than base material was obtained with appropriate welding parameter combinations, having a revolution of 1,120 rpm, compressive tool force of 4.5 kN, traverse speed of 125 mm min−1, and tool tilt angle of 0°. Best welding parameter combinations resulted in ultra fine grain structures in the welding zone and high-quality welded joint.

Effects of dilution and baseplate strength on stress distributions in multipass welds deposited using low transformation temperature filler alloys

Transformation plasticity can be utilised to control residual stresses in steel welds. This requires special filler alloys that transform at a sufficiently low temperature to compensate for accumulated thermal contraction strains. However, the welding parameters needed to optimise the effect in multipass joints have yet to be established. This topic has been investigated by characterising the residual stress distribution in multipass welds fabricated with different welding alloys and baseplates using neutron diffraction to assess the effects of dilution and baseplate strength. While the use of richly alloyed weld metal does enhance fatigue performance in single pass joints, the extent of stress relief that can be derived from transformation plasticity is reduced due to incomplete martensitic transformation when further layers are deposited. For all cases studied, compressive stresses were measured in the weld metal with balancing tensile stress in the heat affected zone of the plate. The magnitude of the tension was observed to be a function of the strength of the baseplate. Recommendations are also presented for the combination of welding and material parameters that lead to the optimum exploitation of transformation plasticity as a method for boosting the fatigue performance of multipass welded joints.

A New Direction for Optimizing the Weld Pool Geometry in Welding of HSLA Steel

This paper reports on process parameter selection for optimizing the weld pool geometry in the metal inert gas welding of High strength low alloy (HSLA) steel. The experimental studies were conducted under varying Voltage, flow rate, stick out and wire feed speed. The settings of welding parameters were determined by using the Taguchi experimental design method. The level of importance of the welding parameters on the weld pool geometry is determined by using analysis of variance (ANOVA). The optimum welding parameter combination was obtained by using the analysis of signal-to-noise (S/N) ratio. The confirmation tests indicated that it is possible to optimize the weld pool geometry significantly by using the Taguchi method. The experimental results confirmed the validity of the used Taguchi method for enhancing the welding performance and optimizing the welding parameters in the metal inert gas welding process.

Experimental Determination of Cooling Rate and its Effect on Microhardness in Submerged Arc Welding of Mild Steel Plate (Grade c-25 as per IS 1570)

An experiment based thermal analysis has been performed to obtain the thermal histories, which can be applied to determine cooling rate of weldment. During fusion welding process it is possible to determine temperature at any point by using thermocouple and from such data it is possible to draw thermal histories for any point of interest, such thermal histories can be utilized to determine cooling rate. The temperature distribution and cooling rate during the welding process have significant effect on the mechanical and metallurgical properties of a weldment. The changes in microstructure, grain growth and hardness in a weldment are very dependent on the temperature distribution and cooling rate. These studies are utilized to investigate the micro-structure and microhardness of the heat affected zone (HAZ) and weldment. In present work, the influence of heat input and cooling rate on microhardness has been investigated. Full factorial design is used to conduct the experiment with three factors and two levels. Eight combinations and two set of heat input are designed with different combinations of SAW welding parameters. Temperature distribution curves and cooling rate have been drawn. The effect of selected welding parameters (Wire feed rate, Open circuit Voltage and welding Speed) on the microhardness have been investigated.

Metallurgy and mechanical performance of AZ31 magnesium alloy friction spot welds

Microstructural features were studied along the cross-section of AZ31 magnesium alloy friction spot welded joints made using different combinations of welding parameters. Static lap shear testing was performed to evaluate the mechanical properties of the welded joints, and the resulting fracture mechanisms and crack propagation paths were fully examined. Failure load is optimized when the welding procedure is performed with the combination of parameters that maximizes the material mixing, the size of fully metallurgical bonding and simultaneously minimizes the vertical displacement of hook region. The welds demonstrate three failure modes during lap shear testing: through the weld and non-circumferential pull-out modes, in which crack propagation crosses the recrystallized zone, and circumferential pull-out mode, around this zone.

Optimization of weld bead geometry in laser welding with filler wire process using Taguchi’s approach

In the present work, laser welding with filler wire was successfully applied to joining a new-type Al–Mg alloy. Welding parameters of laser power, welding speed and wire feed rate were carefully selected with the objective of producing a weld joint with the minimum weld bead width and the fusion zone area. Taguchi approach was used as a statistical design of experimental technique for optimizing the selected welding parameters. From the experimental results, it is found that the effect of welding parameters on the welding quality decreased in the order of welding speed, wire feed rate, and laser power. The optimal combination of welding parameters is the laser power of 2.4kW, welding speed of 3m/min and the wire feed rate of 2m/min. Verification experiments have also been conducted to validate the optimized parameters.