The project CASSTIR (started up at the end of 2006), funded by the Belgian Science Policy, is a collaboration between BWI, UCL, CEWAC and UGent. The project aimed at stimulating and introducing the innovative friction stir welding technique applied to aluminium alloys in Belgium, as well as obtaining a profound knowledge in this welding process by studying the friction stir joint characteristics into great detail.
During friction stir welding, the weld is created by a rotating tool, consiting of a profiled pin and a shoulder. The pin is moved along the interface between the two plates to be welded. The tool generates the required heat for welding.
Magnetic pulse welding is a new, very innovative but nearly unknown production process. The working principle of the welding process is based on the use of electromagnetic forces to deform and to weld workpieces. Since this sophisticated welding process doesn't use heat to realise the weld, it offers important advantages with regard to the conventional welding techniques!
Recently, an innovatie spot weldin technique has appeared on the market, that use frictional heat to create a joint. Friction spot welding is performed by plunging a rotating tool in the sheets to be welded, which are placed in the overlap configuration. The connection is generated by means of frictional heat and mechanical work. The result is a spot welded lap connection, with minimal material loss and a flat surface with no keyhole.
Friction welding is now well established as one of the most economical and highly productive methods in joining similar and dissimilar metals. It is widely used in automotive and aerospace industrial applications. Friction welding is often the only viable alternative in this field to overcome the difficulties encountered in joining the materials with widely varying physical characteristics. This process employs a machine that is designed to convert mechanical energy into heat at the joint to weld using relative movement between workpieces, without the use of electrical energy or heat from other sources.
High-velocity electromagnetic deformation and welding processes (also know as magnetic pulse forming and welding) are highly innovative automatic production techniques. These processes are based on the same working principle, more specific the use of electromagnetically induced forces to deform, crimp and/or weld workpieces. The electromagnetic pulse joining processes have remarkable advantages compared to the conventional joining processes. The possibilities of the technology is illustrated with some examples.
An innovative welding method for fully automatic joining of pipelines has been developed. The proposed welding procedure is a variant of the conventional friction welding process. A rotating intermediate ring is used to generate heat necessary to realise the weld. The working principles of the welding process are described. The weldability of the micro-alloyed high-strength pipeline steel API-5L X65 is experimentally investigated. It was found that the new welding process is suitable for joining this material. When welding with a sufficiently low heat input, a high weld quality is obtained. Under these circumstances the weld strength, ductility and impact toughness are high and fulfil the requirements of the commonly used standard EN 12732 for joining pipes.