A method includes assessing a plurality of Titanium plates to determine a grain size for each plate and removing all Titanium plates with an average grain size that is larger than a threshold size from the plurality of Titanium plates. One of the Titanium plates remaining in the plurality of Titanium plates after the removing step is then used to form a cathode for an ion pump.

A filament assembly can include: a button having a planar emitter region with one or more apertures extending from an emission surface of the planar emitter region to an internal surface opposite of the emission surface; an inlet electrical lead coupled to the button at a first side; an outlet electrical lead coupled to the button at a second side opposite of the first side; and a low work function object positioned adjacent to the internal surface of the planar emitter region and retained to the button. The planar emitter region can include a plurality of apertures. The low work function object can include a porous ceramic material having the barium, and may have a polished external surface. An electron gun can include the filament assembly. An additive manufacturing system can include the electron gun having the filament assembly.

A conventional method to process a tip fails to designate the dimension of the shape of the end of the tip, and so fails to obtain a tip having any desired diameter. Impurities may be attached to the tip. Based on a correlation between the voltage applied or the time during processing of the end of the tip and the diameter of the tip end, the applied voltage is controlled so as to obtain a desired diameter of the tip end for processing of the tip. This allows a sharpened tip made of a tungsten monocrystal thin wire to be manufactured to have any desired diameter in the range of 0.1 ?m or more and 2.0 ?m or less.

A carburized La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo filament cathode and its fabrication method, which belongs to the technical field of rare earth-refractory metal cathodes. The rare earth oxides are La.sub.2O.sub.3 and Lu.sub.2O.sub.3, and the total concentration of rare earth oxides ranges from 2.0-5.0 wt. %. The La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped molybdenum oxide powers are prepared by Sol-Gel method. La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo powers are prepared by two calcining steps. Then pressing and sintering the mixed powders to obtain the molybdenum rods; operating mechanical and heat processes of the molybdenum rods to obtain molybdenum filament. Operating electrolytic cleaning, straightening, winding modeling and cutting treatments with Mo filament to obtain the un-carburized La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo cathode. And then carburize the filament cathode at a high temperature for a short time to obtain a cathode with high carburization degree. And then operate the out-gassing treatment and activation treatment with the cathode at a high temperature to obtain an environmental and non-radioactive cathode with good emission current and emission stability.

In order to provide a thermionic emission filament capable of ensuring a long life and improving an analysis accuracy of a mass spectrometer using the thermionic emission filament, in the thermionic emission filament including a core member through which electric current flows and an electron emitting layer which is formed so as to cover a surface of the core member, the electron emitting layer is configured to have denseness for substantial gas-tight integrity.

According to one embodiment, an X-ray tube, including a cathode including a filament including a leg portion extending from a coil to a distal portion and including a corner portion at the distal portion, a support terminal including a gap, and including an opening portion in which the gap is opened and a bottom portion located on a side opposite to the opening portion, and a cathode cup being connected to the support terminal, the distal portion being located in the gap, the support terminal including a protruding portion protruding in the gap, being located more closely to the bottom portion side than the distal portion, and being joined to the corner portion of the leg portion.

A flat emitter configured for use in an X-ray tube is presented. The X-ray tube includes a first conductive section including a first terminal. Further, the X-ray tube includes a second conductive section including a second terminal. Also, the X-ray tube includes a third conductive section disposed between the first conductive section and the second conductive section, wherein the third conductive section is configured to emit electrons toward a determined focal spot, and wherein the third conductive section includes a plurality of slits subdividing the third conductive section into a winding track coupled to the first conductive section and the second conductive section, wherein at least two of the plurality of slits are interwound spirally to compose the winding track, and wherein the winding track is configured to expand and contract based on heat provided to the third conductive section.

A cathode for an X-ray tube, an X-ray tube, a system for X-ray imaging, and a method for an assembly of a cathode for an X-ray tube include a filament, a support structure, a body structure, and a filament frame structure. The filament is provided to emit electrons towards an anode in an electron emitting direction, and the filament at least partially includes a helical structure. Further, the filament is held by the support structure which is fixedly connected to the body structure. The filament frame structure is provided for electron-optical focusing of the emitted electrons, and the filament frame structure is provided adjacent to the outer boundaries of the filament. The filament frame structure includes frame surface portions arranged transverse to the emitting direction, and the filament frame structure is held by the support structure.

In order to provide a thermionic emission filament capable of ensuring a long life and improving an analysis accuracy of a mass spectrometer using the thermionic emission filament, in the thermionic emission filament including a core member through which electric current flows and an electron emitting layer which is formed so as to cover a surface of the core member, the electron emitting layer is configured to have denseness for substantial gas-tight integrity.

Aspects include a method for treating a polycrystalline material, the method comprising: exposing a surface of the polycrystalline material to a plasma thereby changing the surface of the polycrystalline material from being characterized by a starting condition to being characterized by a treated condition; wherein: the surface comprises a plurality of crystallites each having the composition MB.sub.6, M being a metal element; the plasma comprises ions, the ions being characterized by an average ion flux selected from the range of 1.5 to 100 A/cm.sup.2 and an average ion energy that is less than a sputtering threshold energy; the starting condition of the surface is characterized by a first average work function and the treated condition of the surface is characterized by a second average work function; and the second average work function is less than the first average work function.