40 results about "Cathode spots" patented technology

A process for producing a tape-like material uniformly containing highly pure single-walled or multi-walled carbon nanotubes and a tape-like material produced thereby; a high-performance field emission electrode including the tape-like material; and a process for producing the field emission electrode. The carbon nanotubes are synthesized by arc discharge, wherein an inert gas or inert gas-containing mixed gas is jetted onto a cathode having a carbon material from the inside of a hollow electrode (11) used as an anode, and simultaneously an arc is generated to form a path of arc discharge along a stream of the gas. At the same time, by relative movement of the electrodes, the cathode spot of the arc is moved on the cathode, and the synthesized carbon nanotubes are formed into a tape.

A method for forming a superhard amorphous carbon coating in vacuum, comprising the steps of: placing an article in a vacuum chamber, evacuating the chamber, treating a surface for the article with accelerated ions; applying, on the treated surface, a layer of a material that provides adhesion for subsequent layers, initiating pulsed electric-arc discharge on a graphite cathode, and obtaining a pulsed carbon plasma stream from a plurality of cathode spots that move along the cathode surface. After that, the carbon plasma is condensed in a predetermined area on the article surface to produce a superhard amorphous carbon coating, the article temperature being maintained within the range of 200 to 450 K through controlling a repetition frequency of the electric-arc discharge pulses. According to the invention, the carbon plasma pulsed stream has average ion energy of 25-35 eV and ion concentration of 1012, 1013 cm-3; axis of the carbon plasma stream being set at angle of 15-45° to a predetermined surface of an article. During application of the coating, the article temperature change Deltat is maintained within the range of 50-100 K.

The invention discloses a preparation method of a CuW70 contact material, comprising the steps of: adding inducing copper powder into tungsten powder in certain proportion and mixing them well, putting the mixed powder into a rubber sheath which is then placed in the high pressure cylinder of a cold isostatic pressing machine so as to be pressed into a skeleton green body, and then preparing the CuW70 contact material through copper infiltration of the sintered skeleton. Due to disappeared copper-rich area and uniform two-phase distribution of the prepared CuW70 contact material by the methodof the invention, the material has rapidly moving cathode spot on the surface, effectively dispersed electric arc, less copper phase splashing, and improved ablation resistance.

The invention belongs to the field of surface modification of materials, and particularly relates to a magnetic control arc ion plating composite depositing process and a magnetic control arc ion plating composite depositing device for controlling the movement velocity of a cathode spot, restraining the transmission of plasma, enhancing the deposition rate and deposition uniformity of a thin film, reducing the spraying of large granules positioned on the surface of a target material and enhancing the etching uniformity of the target material. The arc ion plating device is provided with two magnetic field generation devices, one is arranged behind the target material, and the other one is arranged at the outer side of a plasma transmission channel; thin film deposition is accessorily carried out on the surface of a base body through a coupling magnetic field generated by the two magnetic field generation devices. The magnetic control arc ion plating composite depositing process disclosed by the invention can reduce the spraying of the large granules positioned on the surface of the target material and the quantity of the large granules contained in the thin film through the coupling magnetic field generated by the two coupled magnetic field generation devices, thereby solving the problem of nonuniformity of the plasma on a transmission space in the traditional process, enhancing the utilization ratio of the plasma, enhancing the deposition rate of the thin film and the thickness uniformity of the thin film and providing the effective guarantee for preparing various high-property thin films.

A gas switch includes an anode and a cathode spaced apart from the anode, wherein the cathode includes a conduction surface. The gas switch also includes a plurality of magnets arranged to generate amagnetic field that defines an annular path over a portion of the conduction surface at a radial distance from a switch axis, and a control grid positioned between the anode and the cathode. In operation, the control grid is arranged to establish a conducting plasma between the anode and the cathode, wherein, in the presence of the conducting plasma, a voltage drop between the anode and the cathode is less than 150 volts, and wherein the conducting plasma forms a cathode spot that circles the annular path.

The invention discloses a testing device for material breakdown field strength, which also includes an XYZ three-coordinate support (1), a laser distance measuring instrument (5), and an XYZ three-coordinate support ( 1) and a fixed anode device (8), the fixed anode device (8) is fixed with an anode (4), and the XYZ three-coordinate support (1) is used to fix the tested sample (3) as the cathode; in the vacuum chamber ( 2) A laser distance measuring instrument (5) is arranged on the outside perpendicular to the direction of the XYZ three-coordinate support (1), and the laser distance measuring instrument (5) communicates with the vacuum chamber (2). The invention can carry out precise adjustment and alignment in three-dimensional directions, and can accurately measure the breakdown distance. It can be applied to accurate testing of breakdown field strength and breakdown current of various metal materials or metal matrix composite materials, as well as real-time observation of the occurrence process of cathode spots and the morphology of cathode spots.

The invention discloses a method for controlling a cathode cleaning area in the aluminum alloy welding process. The method is characterized in that during aluminum alloy electric arc welding, when a to-be-welded workpiece is connected with a cathode, three beams of lasers acting on the front face and the two sides of a molten pool correspondingly are adopted for adjusting the range of the cathodecleaning area. According to the method, the width and the cleaning range of the cleaning area can be freely controlled, and damage of too large or too small cathode spot dancing to welding quality isavoided; during corner joint, the cleaning area can be prevented from deviating to a certain side through laser guide; and the requirement for the laser power density is low, and the effect of guidingcathode spots can be achieved through the low-power lasers being about 300 W.

The invention belongs to the field of optics, and discloses a strong light analog light source lighting device, comprising: a light source, a reflective optical system, a light source focusing assembly, a light source heat dissipation mechanism, a wind speed acquisition module, a xenon lamp main control system, a xenon lamp electronic ballast, a direct current Stabilized power supply, light source mobile platform and supporting mechanism. When the device of the present invention is working, turn on the heat dissipation mechanism of the light source, the wind speed acquisition module, the main control system of the xenon lamp, the electronic ballast of the xenon lamp, and the DC power supply in sequence, adjust the output of the electronic ballast of the xenon lamp, slowly light the xenon lamp in the light source, and adjust the light source The three-axis adjustment mechanism in the focusing assembly makes the xenon lamp cathode spot in the light source coincide with the focus of the parabolic mirror in the reflection optical system, and outputs parallel light. By adjusting the output power of the xenon lamp electronic ballast and the DC stabilized power supply, different color temperatures and ambient light with different illuminance can be obtained, which meets the photoelectric parameter measurement requirements of the liquid crystal display in the daylight environment.