With the emergence of industries and their growth, joining different parts to each other has become an important need. Due to the complexity of conventional connection methods, there has been a great deal of interest in research and development of new connection methods in recent years. Therefore, this study was conducted to investigate the joining strength of 5083 aluminum alloy to a polymer-based composite reinforced with carbon black particles. In this study, mechanical properties including shear tensile strength and the effect of reinforcing particles on the thermal conductivity of high density polyethylene were investigated. In this study, the joining was performed by friction stir Welding process and the Weld point strength was investigated by shear tensile test. Percentage of reinforcing phase added to the polyethylene matrix, dwell time of friction stir spot Welding machine tools as variables affecting the shear tensile strength were evaluated in this study. The results showed that by increasing the dwell time for pure polyethylene for 15 seconds and for composite samples of carbon black reinforced polyethylene in a time period of 10 seconds, a favorable bond was established and with increasing dwell time Up to 20 seconds due to excessive increase of polyethylene melt strength and residual stresses during the freezing process, a decreasing trend of bond strength was observed.

With the advancement of the construction industry, the use of high-strength steel has gradually increased. High-strength steels can withstand higher stresses compared to conventional steels, yet they exhibit less ductility. Currently, due to their high cost, they are primarily utilized in specialized industries. Connecting two steel pieces requires the use of Welding or bolts. Fillet Welding is the simplest and most commonly used type of Welding. Therefore, investigating this type of Weld in high-strength steel is of great importance. Fillet Welds can also have different angles in the direction of applied force, which itself affects their strength. In this study, the influence of the Welding angle on the axis of the applied force has been examined. First, an experimental model, considering the effect of defects in the Weld, was modeled and validated using ABAQUS software. Subsequently, specimens were analyzed at various angles. The maximum strength of the Weld and its ductility were investigated. Additionally, the recommended strength of the American steel code for Welds at different angles was examined. The results showed a 14% average difference from the code. Unlike mild steels, an increase in the Welding axis angle with the direction of the applied force increased the ductility of the fillet Weld.

In this study, the tensile strength, impact strength, and the hardness of the Weld are determined. A criterion is proposed for describing the effect of residual stress on the Weld mechanical properties. Dimensionless parameters such as Rya (the average of residual stress over the material yield strength), Rym (the maximum residual stress over the material yield strength), Ru2 (the difference in the residual stress over the material ultimate strength), and Ru3 (the difference ratio between the maximum and minimum of three-dimensional residual stresses over the material ultimate strength) are presented to describe the influence of residual stresses on the actual mechanical behavior of the Welded pipe. Maximum Rya criterion and lowest strength are obtained at the Weld gap center on the external surface of the pipe. The sharp decline in Ru2 criteria is consistent with the severe reduction in impact strength perpendicular to the Weld gap.

In the present study, the ultrasonic Welding process of plastics is used for overlap joining of polypropylene composites reinforced with glass fiber. The effect of three process parameters such as Welding time, air pressure, vibration amplitude and the amount of glass fiber in the composite on tensile- shear strength of Weld joints is investigated. To reduce the number of tests and cost, the response surface methodology of design of experiments is employed by considering the above four parameters at three levels. These parameters are also optimized to obtain maximum Weld tensile-shear strength. The results showed that a maximum failure force of about 2.30 KN is obtained when air pressure, vibration amplitude, Welding time and amount of glass fiber are 1.5bar, 32 microns, 0.4 seconds and 10 percent, respectively.

Welding as a fabrication process can be used to join materials, including composite and nanocomposites and laser Welding process due to its advantages has found wide applications in this field. Its process parameters can play a significant role in determining the Weld strength of laser-Welded joints in polypropylene/clay nanocomposites. In this study, the effect of laser Welding parameters, such as laser power, Welding speed and focal position along with the clay content in a polypropylene/clay nanocomposite on Weld strength were determined using response surface methodology. This methodology was applied for developing a mathematical model which can predict the main effects of the above parameters and their impacts on tensile strength of butt-Welded laser joints in 2-mm thick polypropylene/clay nanocomposite sheets. The analysis of variance was performed to check the adequacy of the developed model. A comparison was also made between the predicted and actual results. The results showed that Weld strength decreased when clay content was increased from 0 to 6 %, but Welding speed increased from 30 to 60 mm/s. The above parameters were also optimized to achieve a high strength Welded joint.

Resistance Spot Welding (RSW) is one of the effective manufacturing processes used widely for joining sheet metals. Prediction of Weld strength of Welded samples has great importance in manufacturing and different methods are used by researchers to find the fracture force. In this article, the Adaptive Neuro-Fuzzy Inference System (ANFIS) is utilized for prediction of joint strength in Welded samples by RSW. A design of experiments (DOE) is prepared according to effective process parameters includes Welding current, Welding cycle, cooling cycle and electrode force. The sheet metal samples prepared from AISI 1075 carbon steel. Tensile test specimens are prepared and the tensile-shear strength of Welded samples are measured. A model is developed according to ANFIS and trained according to teaching-learning based optimization algorithm. 70 % of test data used for network train and the remained 30 % used for access the accuracy of trained network. The accuracy of the trained network was assessed and the results show that the trained network can predict the joint strength with high accuracy. The determination factor (R2) and mean absolute percentage error (MAPE) are 0. 99 and 0. 48 % for trained data and 0. 95 and 6. 2% for test data.

Today, laser Welding technology is one of the new methods in manufacturing. Laser spot Welding is used to connect thin sheets of austenitic stainless steel in the manufacture of kitchenware. The strength and size of the Weld nugget are two important parameters in determining the quality of laser spot Welding. In this study, thin sheets of stainless steel 316 with a thickness of 0. 7 mm were laser spot Welded. To perform this Welding, a medium power Nd: YAG laser Welding machine was used and the effects of effective laser parameters on the strength and size of the Weld button were investigated experimentally. Laser frequency at three levels of 5, 7 and 9 Hz, peak laser power at three levels of 1670, 1750 and 1800 W and pulse ON time at three levels of 6, 8 and 10 milliseconds were selected as parameters and test levels. Taguchi L9 method was used to design the experiments. The experimental results show that with increasing laser power, the diameter of the Welding button decreases, with increasing the pulse ON time, the diameter of the Welding button first increases and then decreases, and with increasing laser frequency, the diameter of the Welding button decreases and then increases. In addition, with increasing pulse ON time and laser frequency, the strength of Weld nugget increases, and with increasing laser power, the strength of Weld button increases firstly and then decreases.

During last ten years, change of consumption pattern, variety and modernity of consumers, variety of producers and competitors, changes and vacillation rates, cause developing and decreasing the amounts of produce expenses by using hardware and software progressing, which are so important. In this respect, one of the possible solutions to increase the quality and enjoy the use of software possibilities is to perform producing systems. The aim of this article is to choose, automatic process and Welding technology by using Weld-EXP. software. In this software, experience and knowledge of skilled men and expert form the rules in the expert system and knowledge base. After interchange of information and receive the necessary data from user, this software by studying and analyzing necessary instances, choose and suggest the best Welding process or processes. Finally, the users confirm and complete it and present the Welding process specification (WPS). Therefore, this way is time-consuming and save the expense of making and producing of Weldments.