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Abstruct-The objective of the project reported in the paper is the design and construction of an experimental high Tc (HTS) synchronous machine. The machine is excited with rare-earth permanent magnets on the rotor and rod-shaped armature conductors on the stator. The machine incorporates Bi-based HTS conductors supplied with electrical contacts. In the design procedure a special attention has been paid to the considerations regarding industrial applications of HTS rotating electrical machines both in motor and generator modes of operation. Possible applications have been analyzed to formulate the requirements for the machine to be applied and calculations have been performed to check how the above requirements can be met by HTS machines. Comparisons have been made between conventional and HTS machines designed for particular practical cases..

Two types of electrodynamic forming process have been developed: electromagnetic and electrohydraulic forming. In the case of electromagnetic forming, the energy stored in a capacitor bank is discharged through a coil, which means that the electrical interaction between the coil and the plate or a tubular part to be formed results in deformation of the workpiece. However, in the case of electrohydraulic forming, the capacitor bank is discharged through a spark gap or filament wire; the deformation of the workpiece is due to the shockwaves, generated by the discharge process in a transmitting medium. In both processes, a large amount of energy is released in extremely short time, therefore these processes are considered to be high energy rate forming processes. These high energy rates, result in increasing the formability of the materials in many cases, and obtain significant deformations also for some materials that normally do not behave plastically. The utilization of the energy stored in the capacitor bank is significantly better in the case of electrohydraulic forming, because the released energy is converted directly to pressure waves, results in forming of higher strength materials. Both metallic and non-metallic materials can be formed by the technologies of electromagnetic and electrohydraulic technologies. In the present paper some aspects and applications of these high energy rate methods are briefly outlined mainly focusing on the automotive industry, involving expansion or compression forming of tubular parts, joining and assembly operations.

Electromagnetic forming is a high speed forming process, wherein the forming pressure is created by high energy density electromagnetic pulse. Besides direct shaping there are other application areas as well, so electromagnetic plastic forming is a potential field of creating joints between tube and rod-like components. Connecting components of dissimilar materials is an increasing demand in the manufacturing process of structures in the automotive industry. The application of new technologies, such as electrodynamic, especially electromagnetic forming, is a possible method to satisfy these demands. The article summarizes the most important fundamentals of electromagnetic forming; in particular, tube-rod joints, the main types of such joints; interference-fit and form-fit joints are described. Experiments, which were carried out producing tube-rod joints with electromagnetic forming, are also introduced. A new type of form-fit joints for tube-rod connections has been developed, which can withstand not only tensile loads but also torsion. Experiments and mechanical tests have proved the applicability of this kind of joints.

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