Abstract: Superconducting, oxidic ceramic materials are worked to filamentary conductors, in that they are filled into silver tubes (2), drawn with the latter to filamentary conductors and then sintered under flowing oxygen. So that such filamentary conductors can be produced industrially with an adequate quality, drawing speed and yield, the silver tube (2) as a sintered sleeve is brought into contact with the ceramic material (1) in a drawing sleeve (3), of soft annealed steel (35) and the resulting sleeve combination undergoes the drawing stages. After drawing the steel drawing sleeve is removed by etching. In a large number of drawing stages, it is necessary to remove the drawing sleeve which has become hard due to the cold working and to replace it by a new, soft annealed sleeve. Simultaneously the sintering sleeve can undergo soft annealing.

Abstract: The disclosed gun is of the type having a housing with a nozzle and a deflecting plate spaced from the muzzle and mounted on a rod axially guided in the muzzle, the annular channel formed between the muzzle and the rod serving as a powder channel. Electrodes extend into the powder channel and are connected to a high voltage source. A stepping motor is connected to the rod to change its axial position, and control means are connected to the motor. Digital circuits inside the housing and manually operable switches permit automatic control or manual control from the gun of the deflecting plate spacing, the voltage, and the powder feed. Indicating means on the gun display the values of the controlled parameters.