Abstract: In an extrusion tool—in particular a disk-shaped pressing die with at least one shaping opening for the extrusion of metal such as aluminum or an aluminum alloy—comprising a steel material—in particular a low-distortion hot-working steel—with a surface coating, the coating on the extrusion tool is made from coating material which is selected from the group containing carbides, nitrides, oxides and combinations of those substances, wherein the coating material is applied to the extrusion tool by a CVD-process.

Abstract: In an extrusion tool—in particular a disk-shaped pressing die with at least one shaping opening for the extrusion of metal such as aluminum or an aluminum alloy—comprising a steel material—in particular a low-distortion hot-working steel—with a surface coating, the coating on the extrusion tool is made from coating material which is selected from the group containing carbides, nitrides, oxides and combinations of those substances, wherein the coating material is applied to the extrusion tool by a CVD-process.

Abstract: Apparatus and method for differentiating between desired synchronous signals and undesired asynchronous response signals in a plurality of secondary radar devices, wherein the interrogation signals are obtained by frequency division from the pulse repetition transmitted rate of the associated primary radar devices which have a pulse repetition rate which is identical or similar to each other and which systems have interference blanking devices to suppress synchronous response signals on the basis of different interrogation pulse repetition rates.

Abstract: A circuit arrangement for the digitalization of the angle of rotation .phi. of a rotatable device which is operated at fa rotations per second, employing auxiliary voltages modulated with sin .phi. and cos .phi. of a fundamental frequency fo, which with the aid of further circuit elements are converted into a counter pulse train which indicates the angle of rotation, in which n pulses correspond to the angle of rotation of 360.degree.; wherein from two auxiliary voltages is formed a third auxiliary voltage which contains only one of the frequencies (fo+fa) or (fo-fa), which third auxiliary voltage and a comparison voltage of the frequency n.sup.. fo are conducted to a comparator circuit, comprising a D-flip-flop, with the comparison voltage being present at the D-input (preparation input) and the third auxiliary voltage being present at the clock-input, whereby the desired counter pulse train with n.sup.. fa is obtained at the output of the D-flip-flop.

Abstract: A radar arrangement utilizes a rotating or pivotal antenna lobe and a primary radar device operating with a doppler evaluation system and a secondary radar device equipped with a rotating or pivotal antenna lobe wherein a certain time period (processing time) expires between the scanning of a recognized target by the lobe of the primary radar antenna and the recognition of this target during the target evaluation in the receiver of the primary radar device. A storage device is provided which captures the azimuth angle position of a target recognized by the primary radar receiver and interrogation signals of the secondary radar transmitter are triggered with the help of a control means associated with the storage device for a certain interrogation range only when the antenna lobe of the secondary radar device repeatedly approaches the target. The interrogation range is selected sufficiently large that a number of answer signals is triggered which suffices for the desired reply probability.