Aluminum alloys have many applications in transportation industry because of their abundance, ease of production, and appropriate mechanical and physical properties. One of these alloys is obtained by combining aluminum with silicon and magnesium (Al-Mg-Si alloys). Since the plates of this alloy are rolled up, heat transfer and crystallization in the heat-affected zone is an important point in their Welding. In this study, we have attempted to investigate Welding-induced recrystallization in this alloy using the finite element method. For this purpose, the physics of the problem was defined and simulated using the ANSYS software. In the next step, the results of theoretical (simulated) and experimental investigations were compared and the effect of current on the size of weld pool and thermal cycle of different samples was assessed. Then, through microscopic examination of different areas of the welded samples, the size of recrystallized area was measured and compared with the results of mathematical calculations. Finally, the hardness of the weld zone and recrystallized area was analyzed. A temperature of 630° C and a holding time of about 0. 3 s will be sufficient for recrystallization of this alloy during Welding.

Resistance spot Welding (RSW) includes many variables that can influence the weld properties. The purpose of this study is to develop an analytical model for prediction of thermal history and weld microstructure in RSW and to find the most important process parameters that influence the weld microstructure. A one dimensional model is proposed for prediction about thermal history during cooling step of RSW process. The reliability of analytical model is evaluated by experiments and numerical simulations. The calculations reveal that the current analytical model is reliable particularly at the temperatures lower than Tm/2. Sheet surface temperature at electrode-sheet interface and sheet thickness are recognized as the most important factors affecting the cooling rate at T

Electroslag Welding is widely used in column joints. However, the process of electroslag Welding has a higher heat input than other Welding processes, which results in dramatic changes in microstructure and mechanical properties, especially grain size and toughness. These connections are very vulnerable when subjected to dynamic loads and earthquakes. Therefore, the study of heat transfers and its effect on the mechanical properties of these joints is important. Considering the importance of this, in the present study, a finite element model is proposed to study the thermal behavior of this process, then the accuracy of the model is measured according to the practical experiments of the microcontroller. For verification, several practical examples of Welding were performed and then, to evaluate the size of the pit pool, welded sections of the macrovar were prepared to confirm the assumptions of the model. In the next step, the validated model is used to study the thermal behavior of the system and the distribution of temperature according to the variables of current, voltage and speed. In this regard, due to the complexity of the process, it is not possible to carry out all simulations with software menus, so much of the simulation was written with the language of the ANSYS software.

Resistance spot Welding is an important manufacturing process in the automotive industry for assembling bodies. The quality and strength of the welds and, by extension, the body is mainly defined by the quality of the weld nuggets. The most effective parameters in this process are sheet material, geometry of electrodes, electrode force, current intensity, Welding time and sheet thickness. The present research examined the effect of process parameters on nugget formation. A mechanical/ electrical/ thermal coupled model was created in a finite element analysis environment. The effect of Welding time and current, electrode force, contact resistivity and sheet thickness was simulated to investigate the effect of these parameters on temperature of the faying surface. The physical properties of the material were defined as nonlinear and temperature dependent. The shape and size of the weld nuggets were computed and compared with experimental results from published articles. The proposed methodology allows prediction of the quality and shape of the weld nuggets as process parameters are varied. It can assist in adjusting Welding parameters that eliminates the need for costly experimentation. This process can be economically optimized to manufacture quality automotive bodies.

Explosive Welding is a process to produce bi- metallic cylindrical components. The process is dynamic and for a chosen geometrical configuration and material properties, is completed in 30m Sec. This paper includes the implication of a finite element engineering package and JWL type pressure- time equation to model the contact response between two similar materials at a very high strain rate - which accurse in explosive Welding of cylindrical components. The simulation employs the FE ABA QUS/Explicit code and the cylindrical components (tube and plug) are assumed to be made from an aluminum alloy, with isotropic work and hardening characteristics. The aim of present research work is to find the important parameters, such as impact velocity of tube to plug, the dynamic angle, the pressure of the explosion at the point of contact between explosive material and tube, the amount of stress and strain in the tube during the deformation. With use of simulation results, various thickness of Aluminum tube and curve plug were explosively welded. The interfacial zone at the welded interface is composed of a wavy structure by intensive plastic deformation of the Aluminum alloy. The weld ability of Aluminum tube is decided by the change in impact velocity and dynamic angle, which are achieved with the geometry of curve plug. Finally the models are validated by the results from explosive Welding experiments.

Ultrasonic Welding is gaining popularity for joining of thin and dissimilar materials and foils in the fabrication of automotive Li-ion battery packs because of excellent efficiency, high production rate, high Welding quality, etc. Precise control of the parameters of the Welding process plays an important role in achieving good joint quality. Numerical simulation can greatly help control the main input parameters such as frequency, clamping pressure, friction coefficient, and vibration amplitude. In this present work, a three-dimensional thermo-mechanical Finite Element (FE) model is proposed using ABAQUS/EXPLICIT for the dissimilar Al to Cu weld to predict the deformation and temperature as output parameters during Welding process by varying input parameters. The simulation results showed that the clamping pressure, vibration frequency and friction coefficient have a great influence on heat production during the process which was critical to determine the final quality of the welded joint. Studies also showed that increased clamping force and Welding frequency led to increased deformation.

Many parameters affect the quality of Welding in the resistance upset Welding (UW) process. These parameters are material and geometry of parts, Welding force, thermal cycle at the weld zone, current density and Welding time. The controllable parameters in this process are current density, Welding time, and Welding force, where current density and Welding time are more significant. In this paper, the effect of Welding time and current density on the temperature distribution of the Welding zone is presented. For this purpose, a thermal-electrical finite element model is developed to analyze the thermal behavior of the joint produced. A transient temperature field obtained from thermal-electrical simulation of UW process is applied as nodal load on the model. The results of thermal-electrical analysis are used to predict the status of the weldment. Specifically, the quality of the weld at the seam can be evaluated. The simulation results are evaluated by performing tensile test on the welded joints. The experimental results show that by increasing in the length of the joint, the maximum tensile load applied to the joint increases.

In this paper, thermal effect of plasma arc Welding is investigated, and temperature field of ferrite stainless steel is acquired. Thermal effect of plasma arc and subsequently the generated temperature field in the work piece is the key for analysis and optimization of this Welding process, which is the main goal of this paper. Finite element simulation of Welding process by SIMPLEC method and ANSYS software is achieved, using FSI solver for getting stainless steel temperature field, effect of parameters variation on temperature field, and process optimization for different situations of plasma and shielding gases (Argon, Helium, and mixture of both). Lastly, the results of other papers are used to verify the correctness of this paper’s results. The temperate field results have determined the effects of Welding parameters, and are used to optimize plasma Welding process for improving weld quality. Optimization results for different gases indicates that due to special heat of Helium gas, there is extra potential with respect to Argon gas to narrow the plasma arc and concentrate inlet heat over stainless steel.

Training is usually carried out throughout traditional methods which impose enormous costs. Virtual reality is one of the most suitable methods that has been presented in this application and improves many of the weak points of traditional training such as high cost of Welding. Previous studies were conducted on virtual Welding with the use of virtual reality techniques in Welding training. The novelty of this article is that uses Kinect for tracking and Adaptive meshing for thermal analysis. The dimension of workpiece is 70x50x10 and the material is low carbon steel. The user performs real-time Welding in the virtual environment by moving the electrode clamp. Since process parameters like current, hand motion speed, arc length, and Welding voltage make changes in generated heat, and color of molten-solid zone, a graphic interface updates the color in each part of the model. The process is modeled in two different ways of fixed and adaptive mesh finite element approaches which manifests good precision and calculation of speed, respectively. All calculations in the simulation environment and the thermal analysis engine performed in the C# program. One of the positive features of the simulator is self-learning. A novice welder could take enough time to learn the manual arc Welding simulator without any extra cost or danger. This simulator provides a good training ability to control the Welding parameters.

Many researchers content themselves with the 2D simulation of Welding process instead of the 3D simulation, because of the time and the cost factors of the latter. In this research, the number of elements and nodes are reduced by an initiative plan (defining an equivalent model) for the simulation of Welding. The Welding process has been simulated by an uncoupled thermal-mechanical finite element model in three steps. Thermal history was determined from thermal analysis, and then the distribution of the metallurgical phase on the fusion and heat affected zones were calculated by a certain code. Afterward, the stress distribution was computed from mechanical analysis, where the material property was defined element by element according to the second step. One of the most important objectives of this simulation is to study the residual stresses of Welding. Comparisons between the thermal analysis results and the metallographic and laboratory results of this research show acceptable accuracy of the proposed method.