摘要:
Two Nb.sub.3 Sn superconducting tapes are overlapped by an amount equal to about two times the width of the superconducting tapes. A filler material of material substantially similar to the tapes is placed between the two tapes in the overlapped region. A NdYAG laser (4) sends a 20-40 watt beam focused by a lens that heats the tapes to create a bridge of superconductivity material formed over the region where the tapes are joined.
摘要:
Methods of making an improved high performance x-ray system having a rotating anode therein which includes an improved target/tubular stem combination which, when combined with a rotor body assembly, reduces tube failure due to anode assembly imbalance and methods of bonding a metallic target and a metal tubular stem and connecting the combination to a rotor body assembly to provide a rotating x-ray tube target are disclosed. An insert of an alloy, for example, tantalum or its alloys, is placed between the target and the niobium-alloy tubular stem and then bonded thereto to produce the x-ray tube target/tubular stem assembly having a high remelt temperature and bond strength which, when connected, such as by bolting to the rotor body assembly, the resulting anode assembly retains proper balance during x-ray tube operations.
摘要:
This invention relates to laser joining of dissimilar materials in order to form an integral structure. Structures of this type, generally, allow circuit breaker components, which are constructed of different materials, to be joined together in order to form an integral circuit breaker.
摘要:
A system for injecting successive beam pulses of a pulsed power laser into optical fibers, for transmission therethrough, is disclosed. The system comprises four lens, four fiber groups with the tips thereof respectively proximate the focal points of the lenses, two galvanometer driven mirrors for directing the laser beam through one of the lenses for focusing onto a selected fiber tip, and control means to drive the galvanometers to reorient the two mirrors between laser beam pulses into successive pairs of predetermined positions effective to inject the successive beam pulses into selected fibers. Failure to reorient the mirrors before the succeeding beam pulse arrives results in laser shutdown. Means are provided for detecting a malfunction of the mirrors, fracture of a lens or a missed fiber injection and, in either case, shutting down the laser.
摘要:
A low-divergence 1.06 micrometer wavelength beam from a total-internal-reflection, face-pumped laser (TIR-FPL) is focused onto the end of a quartz optical fiber to a spot having a size smaller than the fiber diameter and with a beam cone angle less than twice the numerical aperture of the fiber. The fiber transmits the energy to emerge at the other end where it is collimated and focused onto material to be processed. A laser average output power level greater than 400 watts can be transmitted through an optical fiber having a diameter less than 600 micrometers.
摘要:
Polycrystalline alumina bodies have been converted to sapphire by a solid state conversion process in which a localized energy source is used to heat only a portion of the body to a temperature above 1800.degree. C. Using a laser as the energy source resulted in conversion to sapphire in less than an hour. The polycrystalline alumina bodies had a magnesia content below 50 wppm, an average grain size below 100 microns, and a density greater than 3.97 g/cc.
摘要:
This invention relates to a method to selectively mitigate intergranular stress corrosion cracking (IGSCC) by rapid quench melting through the use of a pulsed laser. Such methods of the type, generally, mitigate reactor pipe cracking by rapidly melting the sensitized material to redissolve chromium carbide and then rapidly cooling the sensitized material such that corrosion cracking can be avoided.
摘要:
An optical fiber holder includes a pair of flat, adjacent surfaces. Each of the surfaces includes a straight groove, the grooves opposing so as to form a passage shaped to engage an optical fiber in a snug fit. Means are provided for fastening the two surfaces together. The optical fiber holder is preferably constructed of material transparent to a laser beam at a predetermined wavelength, thereby making the optical fiber holder particularly adapted for use with a laser device generating such a laser beam.
摘要:
Pulse laser energy in the near infrared and visible spectrum is passed through a single fiber optic at power levels required for material and metal processing. A neodymium-YAG laser used in pulsed mode is coupled to the end of a quartz fiber optic which transmits peak powers in the kilowatt range. In order to transmit higher amounts of average power, a prepared fiber end allows beam coupling through core-air and core-cladding zones. The beam at the output of the fiber optic is focused to achieve power densities capable of cutting, drilling, and welding of metals etc. The main advantage is greater flexibility of laser beam manipulation.
摘要:
Laser processes such as cutting, drilling, and welding metals and other materials are performed manually with a hand held fiber optic laser tool. A near infrared or visible wavelength pulsed laser beam is coupled to the tool by a single clad quartz fiber whose ends are prepared to reduce losses and which transmits laser energy with peak powers in the kilowatt range to the output end. The hand held laser tool is comprised of focusing optics for the laser beam, an inert gas supply for welding cover gas, and an oxygen supply for gas assist cutting.