AWS C7.1M／C7.1 pdf free download

AWS C7.1M／C7.1 pdf free download.Recommended Practices for Electron Beam Welding and Allied Processes.
beam ra.stcrlng. A method of high speed beam deflection (kilohertz range or higher) used for simulated multi-beam processing (joint detection, pattern generation, multi-welds, and in situ postweld heat treatment).
beani spot. Apparent size of the beam impingement area on the surface of’ the vorkpiece (working spot size as opposed to focal spot size). See also focal spot.
beam oltage. Magnitude of electrical potential employed to accelerate and increase the energy of the electrons in an electron beam gun (usually expressed in units of kilovolts).
bias cup. Component of a tnode gun, more electrically negative than the cathode, used as a grid to control the beam current and shape the beam. Also referred to as grid cup. See also triode gun.
cathode. The source of electrons, commonly a segment of tungsten or tantalum, heated to a temperature where thermionic emission occurs. Other forms and materials used as thermionic emittcr include buttons or rods of tungsten, tantalum, lanthanum hexaboride, and rare earth oxides. Sec also filament.
CNC. An acronym for comj’aireried ,Vunierical (oiurol.
cold shut. A form of weld discontinuity caused by material solidifying at an interface before the liquid metal on either side of the interface flows together to form a continuous structure.
column alc. A vacuum valve between the electron gun and the work chamber, used to preserve vacuum and prevent contamination of the gun when the chamber is vented. Also referred to as gun valve.
conduction mode. Welding at a power density below that required to form a keyhole. where the primary method of obtaining joint penetration is heat conduction in the material being welded. See also keyhole mode,
concrgcnce angle. The angle formed between the axis of the beam and the outermost electron trajectories as they approach sharp focus.
corona clear. A technique for removing contamination from the electron beam gun by using a higher than nonnal beam voltage. Sometimes referred to as glow discharge cleaning or gun clearing.
cosmetic pass. A partial penetration weld pass made primarily to enhance surface quality and appearance. defocus. To locate the focal spot above or below the workpiece level when welding. See also focus.
degauss. To demagnetize a part or fixture in order to reduce unwanted magnetic fields.
diode gun. An electron beam gun where the cathode and grid cup operate at the same electrical potential.
do nslopc time. Period at end of weld during which the level of weld input power or other parameter is continuously decreased in a controlled manner.
electron beam. Electrons accelerated and shaped into a directed stream by an applied electrical potential.
Hectnrn Beam .\dditivc Manufacturing (EBiM). This process. also known as Electron Beam Free Form Fabrication (EBFFF) or Electron Beam Direct Nianufaciuring (EBDM. makes use of commercially available wire or powder as fcedstock material that is melted by the electron beam. Paris are buik layer by layer on a substrate until a targeted near net shape part is achieved.
Electron Beam Brie Welding (EBBW). A hybrid process that employs an electron beam to simultaneously accomplish welding and brazing, and which is sometimes used in pertorming T-joint welds in order to enhance the structural integrity of the joint being produced.AWS C7.1M／C7.1  pdf download.