摘要:
A filament comprises a generally thin metal component, such as a sheet, ribbon, or foil. The filament comprises at least one emitter, at least one current-condensing structure and a tab on each end of the at least one emitter. Each tab is connectable to a support system, comprising for example a lead and attachment post. When a current is passed through the filament, the current-condensing structure establishes current flow through the filament resulting in a desired temperature distribution across the emitter, for example a substantially uniform temperature distribution. A predictive tool for determining a geometry of a filament to provide a desired temperature distribution is set forth. The filament may be curved, and methods and systems for providing a curved filament are also provided. Attachment systems are further disclosed for attaching an emitter to a support structure.
摘要:
A filament comprises a generally thin metal component, such as a sheet, ribbon, or foil. The filament comprises at least one emitter, at least one current-condensing structure and a tab on each end of the at least one emitter. Each tab is connectable to a support system, comprising for example a lead and attachment post. When a current is passed through the filament, the current-condensing structure establishes current flow through the filament resulting in a desired temperature distribution across the emitter, for example a substantially uniform temperature distribution. A predictive tool for determining a geometry of a filament to provide a desired temperature distribution is set forth. The filament may be curved, and methods and systems for providing a curved filament are also provided. Attachment systems are further disclosed for attaching an emitter to a support structure.
摘要:
A method of lasing a filler wire to weld a first workpiece to a second workpiece comprising first and second materials, respectively, includes positioning a tip of the filler wire above an opening defined by the workpieces. The tip extends over a width of the opening and over a portion of each of the workpieces. The filler wire is preheated and melted by directing a laser beam at the tip. The laser beam is advanced along a length of the opening with the tip positioned under the laser beam to form a high aspect ratio weld between the workpieces. The high aspect ratio weld has an aspect ratio of at least about two. The energy and time required for the laser beam to melt the filler wire is reduced as the filler wire is preheated.
摘要:
An apparatus is provided for resiliently mounting a photomultiplier tube. The tube is sequentially tapped to move a debris particle therein. The tube is initially inclined for moving the particle to a staging site. The tube may then be re-oriented horizontally for moving the debris particle from the staging site to a target site for subsequent laser blasting thereof.
摘要:
An exemplary method for welding a circular disk coaxially atop a tubular body comprises the steps of rotating the body and disk thereon, drawing a vacuum inside the body for vacuum holding the disk thereon, and welding the disk along a rim thereof to the body to sealingly join the disk thereto.
摘要:
A method for welding a first metallic material to a second metallic material where at least one of the first and second metallic materials have at least one surface which has an optical pattern thereon. The method comprises the steps of: arranging the first and second metallic materials into a final position in which they will be welded along a joint; directing focused energy at the joint from a Nd-YAG pulsed laser having an energy output in a range from about 10 Joules to about 30 Joules and a pulse length in a range from about 5 ms to about 9 ms; and traversing the joint at a predetermined welding speed while directing the focused energy such that a weld spot overlap in a range from about 50% to about 90% is maintained, resulting in a welded joint wherein a heat effect zone about the welded joint is minimized further resulting in minimal distortion and damage to an area of the optical pattern proximate to the welded joint. Also provided is a method for repairing any weld defects in the welded joint with the same Nd-YAG pulsed laser.
摘要:
A welding fixture includes a stationary tubular outer manifold having an outer flow passage extending radially therethrough for drawing vacuum, and a tubular spindle extending coaxially therethrough. The spindle includes a mandrel at one end over which the bore of a tubular body is positioned. A sleeve at the opposite end of the spindle is used for rotating the spindle. An inner manifold adjoins the sleeve and is disposed inside the outer manifold, and has an inner flow passage extending radially therethrough and disposed in flow communication with the outer passage for drawing vacuum inside the spindle and in turn inside the body for retaining a disk thereon. An annular flange adjoins the mandrel and the inner manifold, and has a seat facing the mandrel for receiving the body at a complementary counterbore, and also includes a bearing land disposed in contact with the outer manifold for rotation thereon. The spindle is rotated for rotating the body and disk thereon for allowing welding of the disk to the body. Vacuum is drawn in the body through the spindle for vacuum holding the disk to the body during the welding process.
摘要:
A method and apparatus of selecting a predetermined number of pulses from a stream of laser pulses is described. The number of pulses is determined by the operator from the laser pulse repetition rate and the desired number of pulses. The invention comprises synchronizing the laser pulses with the start of the pulse selection, allowing the predetermined count of laser pulses to pass a blocking mechanism; and finally blocking the pulses after the pulses have passed.
摘要:
A laser deposition apparatus is provided which uses a laser beam to manufacture and/or repair a work piece by depositing a material on a work piece and controlling a temperature of the work piece using a laser beam prior to, during and/or after deposition. The temperature controlling laser beam has a larger cross-sectional area than a laser beam used for deposition at the surface of the work piece.
摘要:
Two parts are coaxially aligned at opposing face ends. The parts are temporarily compressed together at the face ends during welding thereof to control size of the resulting weld joint. Temporary compression may be effected by applying a compression force through the parts to abut together the face ends, and then limiting plastic displacement of the parts at the weld joint during welding. The displacement control limits radial expansion at the weld joint in a preferred embodiment.