MIG Hybrid Research Articles

Development of TIG MIG Hybrid Welding Process: A Brief Review

The purpose of this article is to review the TIG MIG hybrid welding process, which benefits from the advantages of conventional MIG welding and TIG welding. The review focuses more on the studies related to the concepts of each welding process, its advantages and disadvantages, and some applications in the industry. The TIG MIG hybrid welding is a new method that is less popular than the conventional welding process. Thus, fewer experimental studies have been conducted on the process. Since the TIG MIG hybrid welding is promising a better welding process and is potent to improve the welding process with a combination of advantages of both conventional MIG and TIG welding, hence more work needs to be done on the TIG MIG hybrid welding research study to provide more valuable information that is lacking so that it could be applied to the industry.

High-Temperature Oxidation of the 304/6061 Welding–Brazing Joint and Its Effects on Corrosion Characteristics

Laser–MIG hybrid welding–brazing was used to weld 304 stainless steel and 6061-T6 aluminum alloy with a thickness of 2 mm. The microstructure, morphology, chemical composition and corrosion behavior of the samples after high-temperature oxidation were investigated. The results reveal that the 304/6061 dissimilar joint had a thicker intermetallic compound layer (7–8 μm) during high-temperature oxidation (HTO) treatment than the sample without HTO treatment (2–3 μm). The oxide film thickness of the 6061 side of the weld joint treated by HTO (2401 nm) increased compared to the samples (181.1 nm) without HTO treatment. Unlike other metals treated by high-temperature oxidation, the high-temperature treatment process in this paper can reduce the corrosion resistance of the base metal and dissimilar joints, and the sequence of the corrosion current density was weld (HTO) >weld>6061 (HTO) >6061>304 (HTO) >304.

An Investigation about Microstructures, Mechanical Properties and Corrosion Behaviour of the TIG - MIG Hybrid Welded Dissimilar UNS 2205 and is 2062 Steels

The connecting of contrasting metals, namely double stainless steel to steel made of carbon, has taken place. performed using a hybrid welding system. A TIG and MIG welding joining based hybrid joining method was designed. The microstructures of the dissimilar metal joints were studied and the grains are coarser as contrast to the use of a single the welding process process by itself. With the addition of TIG welding to the process of MIG welding, the water-holding capacity of the metal in molten state pool is significantly improved. The nominal corrosion behaviour of the weldments was found better than the single arc welding system alone. The passivation behaviour of the joints was in the similar line to that of double stainless steel base metal. The pitting resistance of the joints in 1 M NaCl solution was inferior to the base metals.

Process stability in laser–MIG hybrid welding of aluminum alloys with various laser and arc distances

During laser–MIG hybrid welding process of aluminum alloys, the distance between laser and arc heat source (DLA) is one of the key factors which affect the welding process stability. Weld formation exhibited various penetration depths, since the interaction between laser and arc changed. Hybrid plasma morphology fluctuated significantly at DLA of 0 mm and hybrid plasma height decreased with the increase of DLA. Violent evaporation of droplet and spatters were generated at DLA of 0 mm. Moreover, keyhole fluctuated violently and significant downward flow of liquid metal was induced at the bottom zone of molten pool due to the impact action of droplet. Keyhole fluctuation was suppressed and molten pool stability was improved at DLA of 2 mm.

An improved simulation of temperature field in PMHW of Ti-6Al-4V alloy

This article describes a coaxial plasma–MIG hybrid welding (PMHW) method to improve the welding quality of titanium alloy plates. Aiming at the temperature field analysis of a Ti-6Al-4V alloy plate in the PMHW process, an improved hybrid heat source model capable of accurately characterising the heat input of a hybrid arc on workpieces and the arc deflection phenomenon, is proposed. Experiments were conducted on 4-mm Ti-6Al-4V plates in PMHW surfacing, and a corresponding simulation analysis was performed. To calculate the weld geometry, a weld pool shape was used in accordance with the experimental results. The results showed that, as plasma current increased from 60 to 80 A, the weld reinforcement and offset decreased, and the size of the weld pool increased. Plasma arc power had a greater effect on the length than on the width of the molten pool. Hybrid arcs had a stronger penetrating ability; hence, achieving deep penetration welding and high welding efficiency in the PMHW of the Ti-6Al-4V alloy was easier. Microstructure analysis showed that the Ti-6Al-4V alloy base metal zone was organised by α- and β-phase transformations; β grains in the weld zone were internally formed by a mixture of Weischer tissue and net basket tissue; and the size of β grains in the heat-affected zone decreased with the increase in the distance from the weld.

Strength Evaluation of Welded Aluminum T-joints, as a Function of Its Welding Process, Execution, Filler Material, and Weld Root Penetration

Essential requirements for weld seams are the long-term transmission of static and time-varying forces. Requirements for the verification of laser welded fillet weld T-joints are proposed in this paper, since there is no established procedure in this field for laser welding. More precisely, the strength of laser MIG hybrid welded AlMg3Mn T-joints, made from 3.5 mm thick sheet metal are determined, depending on the penetration of their weld root gap. This allowed the unwelded root gap to be related to the decrease in strength, even though this is more apparent with dynamic than with static loading. In addition, the influence of filler material, single and mutual-sided MIG welds have been added to this comparison. Filler materials used are the related AlMg2.7Mn or the extraneous AlSi5.

KTIG–MIG hybrid arc welding process

Metal-inert gas welding is an important welding process but the process instability easily induces spatter and undercut defects. To improve the welding process stability, a new hybrid arc welding process, named KTIG–MIG, was proposed in this paper. Arc characteristics were preliminarily studied. It is found that in KTIG–MIG hybrid welding, MIG arc is stable even it is shielded with pure argon gas; stable spray transfer is easily achieved in a much wider process window, especially the lowest voltage to achieve spray transfer is greatly reduced; KTIG arc voltage decreases than that in single KTIG arc, and MIG arc current is higher than the pre-set value. Cooling state of the KTIG tungsten plays a key role in slowing tungsten erosion.

Investigation of microstructure, mechanical, and corrosion properties of Inconel 617 joints welded by laser–MIG hybrid welding

The demand for Nickel-based superalloy of Inconel 617 material is increasing for manufacturing hot section components of gas turbines, chemical, and nuclear power plants. It has excellent corrosion resistance in high-temperature environments. In the present study, laser–MIG hybrid welding consisting of a 3.5 kW CO2 laser in combination with a MIG welding system was utilized to weld 10 mm thick Inconel 617 plates with the wire feed rates (WFR) of 10 and 11 m/min in a single pass to analyze the welds microstructure, mechanical, and corrosion properties. The results revealed that the microstructure of the weld zone is composed of cellular crystals with dendrites and equiaxed sub-grains. Electron backscattered diffraction (EBSD) studies revealed coarse columnar dendrites and equiaxed grains at the center of weld joints with the same crystallographic orientation across the fusion boundary. The XRD analysis revealed the dominant gamma and gamma prime (γ/γ′) [(Ni/Ni3(AlTi))] phases along with the presence of minor carbide peaks such as Ti (C, N), M23C6, Cr (C, N), and M6C. The BM has a lower hardness (232 HV) and higher impact energy (236 J) than the weld joints. Similarly, the increase in WFR results in a decrease in microhardness (268–256 HV) values and an increase in impact energy (199–212 J). The weld joints exhibit good bend ductility without any cracks. The potentiodynamic polarization results revealed a lower corrosion rate of 0.212 mpy for the base metal than for the weld joints. The increase of WFR increased the weld metal corrosion rate from 0.342 to 0.427 mpy due to an increase in heat input (0.516–0.615 kJ/mm) and solidification time, which caused the coarsening of the grains resulting in lower grain boundary density and anode reaction to accelerate, which deteriorated the corrosion resistance of the welds.

Experimental and finite element simulation for thermal distribution in TIG, MIG and TIG-MIG hybrid welds

Experimental and finite element simulation for thermal distribution in TIG, MIG and TIG-MIG hybrid welds

Evaluation of welding process stability and weld formation during laser-MIG hybrid welding

In laser-MIG hybrid welding, the visual information can be used to monitor the stability of the process and estimate the weld formation. Taking the hybrid welding of ER308 stainless steel as an example, a high-speed camera is used to simultaneously obtain visual information of top and bottom of the weldment during the welding process. Combined with the visual characteristics of arc light, molten hump and spatter at the bottom, the influence of various welding state characteristics on weld formation was analyzed. The comparison between the welding process of good weld and root humps illustrated that the time series curves of the area and centroid coordinates of the molten hump at the bottom can reflect the formation process of the root humps. The main cause of root humps is the lack of heat input. The results support a basis for monitoring and controlling the laser–MIG hybrid welding process status.

Behavior and stability of droplet transfer under laser-MIG hybrid welding with synchronized pulse modulations

In order to explore the synergetic effect on the process combination of pulsed laser and pulsed MIG hybrid welding, two kinds of coupling modes were performed by modulating the laser power to synchronize the arc current. The results showed that under the in-phase coupling mode, the addition of a high power laser during the peak period of the arc current increased the formation and separation time of the droplet and resulted in the deviation of droplet from the wire axis. This caused the droplet to be easily hit by the laser beam and reduced the stability of the droplet transfer. Moreover, the enlarged laser-induced plasma led to a significant loss of the laser energy. In contrast, under the anti-phase coupling mode, the application of a low power laser during the period of the highest arc current suppressed the arc length becoming longer and resulted in faster droplet separation, fewer weld spatters and smoother droplet transfer. At the same time, compared with the weld of in-phase laser-MIG hybrid welding, the weld of anti-phase laser-MIG hybrid welding had the advantages of deeper penetration, fewer weld spatters, less porosity and better tensile properties.

An Experimental Study on the Effect of Heat Input on the Weld Efficiency of TIG-MIG Hybrid welding of Type 304 Austenitic Stainless Steel

Welding is described as the process of joining metals so that bonding can be created as a result of inter-atomic penetration. This study investigated the impact of heat input on the efficiency of the welding joints of 304 stainless steel. Three welds joint were made from two similar 304 stainless steel plates of thickness 6 mm. The tensile strength outcomes acquired showed that apex average magnitude of 672 MPa is obsessed by the sample A1 with lower thermal input. It was discovered that the percentage elongation, tensile strength and weld joint efficiency decreased with the intensification in thermal input into the weld. The average % elongation for the entire samples ranged from 28.4 % to 36.5 %. Sample A1 had the highest joint efficiency of 94.5 %. However, the optimum welding current of 190 for TIG and MIG hybrid welding of type-304 austenite stainless steel can be recommended for advanced technological applications such as aircraft manufacturing, nuclear industry, automobile industry and processing industry.

Neural networks based prediction modelling of hybrid laser beam welding process parameters with sensitivity analysis

Present paper attempted to model complex relationship between CO2 laser–MIG hybrid welding parameters and it has been completed using different algorithms of artificial neural networks (ANN). Input parameters for the study include laser power, welding speeds and wires feed rate and tensile strength of the joint is considered as output. A full factorial experimental dataset is used for the purpose. Variants of back propagation neural networks (BPNN) and Radial Basis Function Networks have been used as training algorithm. Altogether 65 different ANN architecture have been trained and tested using 6 different training algorithms to find out ANN with best prediction capability. 3-11-1 ANN architecture trained using BPNN with Bayesian regularization shows best prediction capability (mean square error 3.24E − 04) and considered as Best ANN. That ANN will be useful for determining required value of welding process parameters to yield a specific welding strength and suitable for online process monitoring and control. Finally, a sensitivity analysis has been conducted and it is found that, maximum welding strength can be obtained with low wire feed rate (4 m/min), low welding speed (2 m/min) and high laser power (3 kW).

Effects of Solution Treatment Temperatures on Microstructure and Mechanical Properties of TIG–MIG Hybrid Arc Additive Manufactured 5356 Aluminum Alloy

A novel additive manufacturing method with TIG–MIG hybrid heat source was applied for fabricating 5356 aluminum alloy component. In this paper the microstructure evolution, mechanical properties and fracture morphologies of both as-deposited and heat-treated component were investigated, and how these were affected by different heat-treated temperature. The as-deposited microstructure showed dominant equiaxed grains with second phase, and the size of them is coarse in the bottom region, medium in the middle region and fine in the top region owing to different thermal cycling conditions. Compared with as-deposited microstructure, the size of grain becomes large and second phases gradually dissolve in the matrix as heat-treated temperature increase. Different microstructures determine the mechanical properties of component. Results show that average ultimate tensile strength enhances from 226 to 270 MPa and average microhardness increases from 64.2 to 75.3 HV0.1 but ductility decreases from 33 to 6.5% with heat-treated temperature increasing. For all components, the tensile properties are almost the same in the vertical direction (Z) and horizontal direction (Y) due to equiaxed grains, which exhibits isotropy, and the mechanisms of these are analyzed in detailed. In general, the results demonstrate that hybrid arc heat source has the potential to fabricate aluminum alloy component.

Effects of different welding process on the electronic temperature of plasma and weld shape during laser-MIG hybrid welding of A7N01P-T4 aluminum alloy

In this paper, the authors investigated on the spectral characteristics of A7N01P-T4 aluminum alloy in MIG, laser, and laser-MIG hybrid welding; calculated the electronic temperature of the welding plasma; and analyzed the difference of three kinds of welding processes with the weld shape. The influence of the oxide film on the spectral characteristics and weld shape of the laser-MIG plasma was investigated. The authors made further research of different welding parameters (laser power, wire feeding speed, and shielding gas flow) on the spectral characteristics of laser-MIG plasma and the weld shape, and then explained the relationship between the plasma and the weld shape. The results are indicated: when the laser power increased from 1 to 4 kW, the spectral intensity, electronic temperature, weld penetration, and weld width increased. When the wire feeding speed increased from 9 to 18 m/min, the spectral intensity, the electronic temperature, weld penetration, and weld width increased. When the shielding gas flow increased from 20 to 40 l/min, the plasma temperature, the penetration depth, and weld width increased. When the protective gas flow increased from 40 to 50 l/min, the electronic temperature, weld penetration, and weld width all decreased, but the argon spectrum intensity and the number of argon atom both increased. In the absence of oxide film, the laser-MIG plasma temperature, the weld penetration, and weld width increased.

Numerical simulation of flow field in the Invar alloy laser–MIG hybrid welding pool based on different heat source models

PurposeThe purpose of this paper is to establish a three-dimensional flow field model of the Invar alloy laser–metal inert gas (laser–MIG) hybrid welding process to investigate the influence of different heat sources between different layers and to analyze the flow field based on the two different heat source models for the multilayer welding.Design/methodology/approachThe Invar steel plates with 19.5 mm thickness are welded into three layers’ seam using the hybrid laser–MIG welding technology. The flow field based on different heat source models is studied and then used to investigate the influence of different heat sources in different layers during the laser–MIG hybrid welding process. The simulation results of flow field using two different heat source models are compared with experiments.FindingsThe flow field simulations results show that using the Gaussian rotating body heat source model to simulate the temperature field is more consistent with the experiment of the hybrid laser–MIG welding where its flow field between different layers better reflects the characteristics of the hybrid laser–MIG welding.Originality/valueThe findings will be useful in the study of a variety of thick-plate laser–MIG hybrid welding process fluid flows.

Effects of coupling between the laser plasma and two arcs on metal transfer in CO2 laser double-wire MIG hybrid welding

CO2 laser double-wire MIG hybrid welding with direct current is a kind of process with high metal deposition rate and large weld penetration. Microscopic interaction model between the laser plasma and two arcs is proposed. Forces acting on the laser plasma and droplet were analyzed. A high speed camera system and an electrical signal acquisition system were used to investigate the coupling and metal transfer. The theoretical analysis and experimental results reveal that when the electromagnetic force of the leading arc on the laser plasma (FLP) is generally equal to the electromagnetic force of the trailing arc on the laser plasma (FTP), there is higher electron density in two lower sides of the laser plasma. Therefore, despite the great electromagnetic force, the two arcs do not deflect from the wire axis. A stable, spatter-free spray transfer can be achieved. When FLP > FTP, there is higher electron density in the upper left side and the lower right side of the laser plasma. Consequently, the trailing arc will deviate from the wire axis under the influence of the electromagnetic force, resulting in an unstable metal transfer with large spatter. Similarly, when FLP < FTP, there is an unstable welding process in the leading arc.

Numerical Analysis of Welding Residual Stress in Laser+MIG Hybrid Butt Welding of Medium- thick Aluminum Alloy

Numerical Analysis of Welding Residual Stress in Laser+MIG Hybrid Butt Welding of Medium- thick Aluminum Alloy

The influence of energy distribution factor during laser-MIG hybrid welding of Invar alloy

In this study, a three-dimensional (3D) finite element model was established to predict the shape of the molten zone and the temperature fields of multi-layer laser–MIG hybrid welding for Fe36Ni Invar alloy. The multi-layer laser–MIG hybrid welding experiments of 19.05-mm-thick Invar plates were conducted to obtain the well-welded joints. The molten zone shapes were compared to the simulated results to figure out the relation between the energy distribution factor and the welding temperature field. A combined heat source model was proposed to describe the interaction between laser heat source and arc heat source. Besides, the empirical formula of energy distribution factor was given. The metallography detection results showed that the increasing ratio of laser power in hybrid welding could increase the weld penetration depth and the increasing ratio of arc power in hybrid welding could increase the weld width. In addition, it was also found that the laser heat source in hybrid welding heat source contributed equiaxed grains, and weld centerlines had rotation, due to different ratios of energy distribution during the multi-layer laser–MIG hybrid welding.

Intermediate layer, microstructure and mechanical properties of aluminum alloy/stainless steel butt joint using laser–MIG hybrid welding–brazing method

Butt joining of AA6061 aluminum (Al) alloy and 304 stainless steel of 2-mm thickness was conducted using laser–MIG hybrid welding–brazing method with ER4043 filler metal. To promote the mechanical properties of the welding–brazing joints, two kinds of intermediate layers (Al–Si–Mg alloy and Ag-based alloy) are used to adjust the microstructures of the joints. The brazing interface and the tensile strength of the joints were characterized. The results showed that the brazing interface between Al alloy and stainless steel consisted of double layers of Fe2Al5 (near stainless steel) and Fe4Al[Formula: see text] intermetallic compounds (IMCs) with a total thickness of 3.7 [Formula: see text]m, when using Al–Si–Mg alloy as the intermediate layer. The brazing interface of the joints using Ag-based alloy as intermediate layer also consists of double IMC layers, but the first layer near stainless steel was FeAl2 and the total thickness of these two IMC layers decreased to 3.1 [Formula: see text]m. The tensile strength of the joints using Al–Si–Mg alloy as the intermediate layer was promoted to 149 MPa, which was 63 MPa higher than that of the joints using Al–Si–Mg alloy as the intermediate layer. The fractures occurred in the brazing interface between Al alloy and stainless steel.