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In this research, a comparison between Soldering and Brazing welding of pure copper metal using a (Zn-Sn) alloy filler was numerically investigated. The welding operations on the eight pieces with dimension (30mm x 20mm x 2mm) were carried out used (Auto Desk Inventor program) to prepare four samples, while the simulation was conducted on these samples by utilized the (COMSOL Multiphysics 4.1 program) to investigate the heat distribution and tensile stress. The simulation study results showed that the thermal distribution of Soldering welding was less than that of the Brazing welding in the area between (40-60 mm) and the maximum temperature of Soldering welding in that region was (405 °C), while the highest temperature for the Brazing welding in the same area reaches to (449 °C). The total displacement of the Soldering welding was up to1.9 x10-7 mm greater than that of the Brazing welding when the shedding stress equal to 5x104 N/ m2

Purpose: The present work aims to investigate the influence of CO2 laser spot welding (LSW) parameters on welding profile and mechanical properties of lap joint of AISI 321 thin sheet metals, and analyze the welding profile numerically by finite element (FE) method. Design/methodology/approach: The weld carried out using 150 W CO2 continues wave laser system. The impact of exposure time and laser power on the welding profile was investigated using an optical microscope. Microhardness and tensile strength tests were used to evaluate the mechanical properties of the joint. Ansys software was utilized to simulate the welding profile numerically. Findings: The results revealed that 2 s exposure time and 50 W power have led to uniform welding profile and highest shear force (340 N), lower hardness gradient across the heat affected zone (HAZ) and fusion zone (FZ). Finite element (FE) analysis of the welding profile showed good agreement with experimental analysis. Research limitations/implications: The selection of laser spot welding parameters for thin sheet metal was critical due to the probability of metal vaporisation with extra heat input during welding. Practical implications: Laser welding of AISI 321 steel is used in multiple industrial sectors such as power plants, petroleum refinement stations, pharmaceutical industry, and households. Thus, selecting the best welding parameters ensures high-quality joint. Originality/value: The use of CO2 laser in continuous wave (CW) mode instead of pulse mode for spot welding of thin sheet metal of AISI 321 austenitic stainless steel consider a real challenge because of the difficulty of control the heat input via proper selection of the welding parameters in order to not burn the processed target. Besides, the maintenance is easier and operation cost is lower in continuous CO2 than pulse mode.

Dissimilar arc stud welding is one of the most important tasks in manufacturing processes used to join the various metals with different dimensions. In the present work, AISI 304 austenitic stainless steel studs were joined to AISI 1008 low carbon steel base plate using an arc stud welding technique. The quality performance of the weld joint was analyzed employing the bending and torque test. A range of welding current and welding time were used to elucidate the effect of welding parameters on weld quality corresponding to bending and torque strength. The statistical method based on the Taguchi technique was applied for determining the optimum parameters. The results revealed that welding time play important role in arc stud welding followed by welding current. The actual torque of 90 N.m can be obtained according to the optimum condition for the stud welding by using (DOE) at 600 AMP and 0.3 second.

Junction temperature is an important parameter in thermal management of LEDs (Light emitting diodes) system. The junction temperature of three different types of LED is calculated numerically. Three dimension numerical simulation using ANSYS-Icepak 15 software package is presented for all cases. Appropriate heat sink is designed for each type of LED and investigates the effect of the fins height on the junction temperature. The increasing in electrical current utilized to driving the LEDs has concentrate high notice on the thermal management in the evolution of LED system. A felicitous design should have minimum thermal resistance between the heat sink base and the junction that depends on conduction heat transfer. The results showed the increase in a heat sink height 10% dissipate more heat transfer from the LEDs system at approximately 15%.