Conventional Non Destructive Testing (NDT) techniques for assessing the weld quality are applied after welding is completed. It results in wastage of time, material and manpower. These inherent limitations of the conventional welding processes can be overcome with an automated adaptive welding system to correct the deviation in the welding current and torch speed to provide defect free welds. T...

The Resistance Spot Welding (RSW) process requires simultaneous application of high electrical current and appropriate pressure over short periods in order to keep the molten material inside the weld zone. Values of these parameters vary in function of the characteristics of the materials to be welded. The application of the electrical current is by means of two copper electrodes brought in con...

Welding is used in a wide range of heavy and light industry, construction and maintenance, including vehicle construction. Workers using welding processes are exposed to electromagnetic fields (EMF). The International Commission on Non-Ionizing Radiation Protection (ICNIRP) has published guidelines on limits of the exposure to static magnetic fields and on guidelines limiting the exposure to ti...

Ultrasonic testing is one of the most popular non-destructive methods to determine the quality in spot welds. The next step of this technology is to be able to determine the quality while the weld is being made, this advance can have a great impact on the quality assurance of joints in materials like aluminum, where the spot welding process is a difficult task. In our approach, a state-of-the-a...

Laser beam welding (LBW) is one of the most important manufacturing processes used for joining of materials. It is also a remarkably complicated, nonlinear operation involving extremely high temperatures. Since its invention more than two decades ago, laser beam welding has been more of an art than a science. Laser welding of austenitic stainless steel AISI 304 the candidate material of this re...

Using tensile tests, this study investigated differences in the welding strength of casts of cobalt-chromium and gold alloys resulting from changes in the voltage and pulse duration in order to clarify the optimum conditions of laser irradiation for achieving favorable welding strength. Laser irradiation was performed at voltages of 150 V and 170 V with pulse durations of 4, 8, and 12 ms. For c...

The overall aim of this paper is to determine optimum position of welding point and number of spot welding in the structure to obtain good characteristics of vibration and noise. For this purpose, two kinds of loss factor were adopted. One is loss factor of sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it is poss...

The in-process changes of weld nugget growth during the Resistance Spot Welding were investigated based on the resistance of input electrical impedance. To compute the time varying resistance of input electrical impedance, the welding voltage and current signals are measured simultaneously and then converted into complex-valued signals by using Hilbert transform. Comparing with the dynamic cont...