The application of laser ultrasonic technique is developed for evaluation of friction stir spot welding (FSSW) quality. The features of laser-generated ultrasonic waves in good welding and incomplete fusion area are simulated by finite element method (FEM). The non-contact laser ultrasonic inspection system (LUIS) was established to verify the numerical results. The interaction of laser ultraso...

Fraunhofer Institute for Laser Technology had developed the SHADOW welding technique, in which high speed joining with minimal distortion is possible using a pulsed Nd:YAG laser. The possibility of high speed, high quality welding had been also reported by use of a single-mode fiber laser. The combination of micro-beam and high speed laser scanning offers potential advantages for thin metal she...

Laser welding has been increasingly utilized to manufacture a variety of components thanks to its high quality and speed. For components with complex shapes, the welding position needs be continuously adjusted during laser welding, which makes it necessary to know the effects of the welding position on the quality of the laser welds. In this paper, the weld quality under two (flat and horizonta...

In order to obtain a good result in the laser welding process, the laser welding technology for manufacturing an automobile body is studied in this research. The robot, the seam tracking system, and CW Nd:YAG laser are used for the laser welding robot system. Especially, the development of the laser-stripe sensor is highlighted. The laser-stripe sensor can measure the profile of the welding obj...

To address control difficulties in laser welding, we propose the idea of a self-learning and self-improving laser welding system that combines three modern machine learning techniques. We first show the ability of a deep neural network to extract meaningful, low-dimensional features from high-dimensional laser-welding camera data. These features are then used by a temporal-difference learning a...

Laser welding with CO2, fiber and various types of solidstate lasers is a well established process currently utilized in a wide range of industries and applications. However, recent technological developments in high power diode laser technology have expanded the capabilities of laser welding, as well as changed its cost characteristics. As a result, diode lasers are poised to replace tradition...

Development of techniques for joining and welding materials on a micrometer scale is of great importance in a number of applications, including life science, sensing, optoelectronics and MEMS packaging. In this paper, methods of welding and sealing optically transparent materials using a femtosecond fiber laser (1 MHz & 1 μm) were demonstrated which overcome the limit of small area welding of o...

Laser welding has been considered as a promising method to join sintered NdFeB permanent magnets thanks to its high precision and productivity. However, the influences of laser welding on the magnetic property of NdFeB are still not clear. In the present paper, the effects of laser power on the remanence (Br) were experimentally investigated in laser spot welding of a NdFeB magnet (N48H). Resul...

Tungsten inert gas (TIG) welding, also called as gas tungsten welding 1. (a) Schematic of TIG welding Process (b) Variety of tungsten electrodes. The activated TIG (ATIG) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid. Tungsten inert gas welding, TIG is widely applied in manufacturing process for different The ...

In order to automatically evaluate the welding quality during high-power disk laser welding, a real-time monitoring system was developed. The images of laser-induced metal vapor during welding were captured and fifteen features were extracted. A feature selection method based on a sequential forward floating selection algorithm was employed to identify the optimal feature subset, and a support ...