Laser welding has been applied to various industries, in particular, automotive, aerospace and microelectronics. However, traditional off-line testing of the welds is costly and inefficient. Therefore, on-line inspection systems with low cost have being developed to increase productivity and maintain high welding quality. This paper presents the applications of acoustic, optical, visual, therma...

In this paper, a three-dimensional finite element model has been developed to simulate the laser-TIG hybrid welding (HLAW) of stainless steel 1.4418 with thickness of 4 mm. Transient temperature profile and dimensions of the fusion zone and heat affected zone (HAZ) during welding process are calculatedusing finite element method (FEM) and were solved in the ABAQUS/Standard software.The heat sou...

In this paper, a three-dimensional finite element model has been developed to simulate the laser-TIG hybrid welding (HLAW) of stainless steel 1.4418 with thickness of 4 mm. Transient temperature profile and dimensions of the fusion zone and heat affected zone (HAZ) during welding process are calculatedusing finite element method (FEM) and were solved in the ABAQUS/Standard software.The heat sou...

Welding of zinc coated sheets in zero gap configuration is of eminent interest for the automotive industry. This Laser welding process would enable the automotive industry to build auto bodies with a high durability in a plain manufacturing process. Today good welding results can only be achieved by expensive constructive procedures such as clamping devices to ensure a defined gad. The welding ...

In this paper, welding of dissimilar metals was demonstrated for the first time, to the best of our knowledge, by using a high-energy high-repetition-rate femtosecond fiber laser. Metallurgical and mechanical properties were investigated and analyzed under various processing parameters (pulse energy, repetition rate, and welding speed). Results showed that the formation of intermetallic brittle...

The performance of laser welding of Ti and two dental precious alloys (Ag-Pd-Au, Au-Pt-Ag) was investigated by mechanical testing and microscopic observation, using butt joint as design. The laser irradiation was done using a commercial Nd:YAG dental laser-welding device in a single pulse mode with output currents 150, 200, 250, 300A, spot diameters 0.6, 0.9, 1.2mm, and pulse duration 10ms. The...

Previous reports of ultrafast laser welding of glass-to-glass have indicated that a pre-existing optical contact (or very close to) between the parts to be joined is essential. In this paper, the capability of picosecond laser welding to bridge micron-scale gaps is investigated, and successful welding, without cracking, of two glasses with a pre-existing gap of 3 µm is demonstrated. It is shown...

The weld pool is the core of the welding process where complex welding phenomena originate. Skilled welders acquire their process feedback primarily from the weld pool. Observation and measurement of the three-dimensional weld pool surface thus play a fundamental role in understanding and future control of complex welding processes. To this end, a laser line is projected onto the weld pool surf...