摘要:
System, computer software and method for determining a susceptibility to reheat cracking of a sample of material, which includes a welded area. The method includes measuring a length of the sample, applying a first stress to the sample to achieve a predetermined elongation of the sample, exposing the elongated sample to a predefined heat treatment, applying a second stress to the sample until the sample breaks at least into two different pieces, and determining the susceptibility of the broken sample to reheat cracking.
摘要:
System, computer software and method for determining a susceptibility to reheat cracking of a sample of material, which includes a welded area. The method includes measuring a length of the sample, applying a first stress to the sample to achieve a predetermined elongation of the sample, exposing the elongated sample to a predefined heat treatment, applying a second stress to the sample until the sample breaks at least into two different pieces, and determining the susceptibility of the broken sample to reheat cracking.
摘要:
In the field of the production of very high frequencies, for example from 1 gigahertz to several terahertz, by beating the frequencies of two laser beams together, a device includes a resonant optical cavity having very stable dimensions receiving the beams, with for each beam, an interrogation device of the resonant cavity supplying an electrical signal representing the difference in frequency between the light frequency of the beam and a resonance frequency of the resonant cavity. The frequency of each beam is servo controlled to minimize the frequency difference observed. The laser beams are produced by a dual-frequency laser producing two beams of different frequencies and orthogonal polarizations. A polarization separator is used for separate servo control of the beams according to polarization, and a polarizer is placed behind a main output of the resonant cavity producing an electromagnetic beam mixing the two polarizations and amplitude-modulated at the beat frequency.
摘要:
In the field of the production of very high frequencies, for example from 1 gigahertz to several terahertz, by beating the frequencies of two laser beams together, a device includes a resonant optical cavity having very stable dimensions receiving the beams, with for each beam, an interrogation device of the resonant cavity supplying an electrical signal representing the difference in frequency between the light frequency of the beam and a resonance frequency of the resonant cavity. The frequency of each beam is servo controlled to minimize the frequency difference observed. The laser beams are produced by a dual-frequency laser producing two beams of different frequencies and orthogonal polarizations. A polarization separator is used for separate servo control of the beams according to polarization, and a polarizer is placed behind a main output of the resonant cavity producing an electromagnetic beam mixing the two polarizations and amplitude-modulated at the beat frequency.
摘要:
Systems and methods provide for wear reduction in a combustion system of a gas turbine. A system for wear reduction includes: at least one substantially H-shaped block, the substantially H-shaped block being configured to secure a transition piece of a gas turbine combustor to a support piece; a first insert including a tungsten carbide in a metal matrix, the metal matrix being selected from a group including cobalt and nickel; and a brazing material which is used in brazing the first insert to the at least one substantially H-shaped block in at least one location on an interior wear surface of the at least one substantially H-shaped block.
摘要:
The invention concerns an oscillator generating a wave composed of a frequency of on the order of terahertz from a beat of two optical waves generated by a dual-frequency optical source (10). The oscillator comprises:a modulator (12) the transfer function of which is non-linear for generating harmonics with a frequency of less than one terahertz for each of the optical waves generated by the dual-frequency optical source,an optical detector (14) able to detect at least one harmonic for each of the optical waves generated by the dual-frequency optical source and transforming the harmonics detected into an electrical signal,a phase comparator (15) for comparing the electrical signal with a reference electrical signal,means (16) for controlling at least one element of the dual-frequency optical source with a signal obtained from the signal resulting from the comparison.
摘要:
The invention concerns an oscillator generating a wave composed of a frequency of on the order of terahertz from a beat of two optical waves generated by a dual-frequency optical source. The oscillator includes a modulator the transfer function of which is non-linear for generating harmonics with a frequency of less than one terahertz for each of the optical waves generated by the dual-frequency optical source, an optical detector able to detect at least one harmonic for each of the optical waves generated by the dual-frequency optical source and transforming the harmonics detected into an electrical signal, a phase comparator for comparing the electrical signal with a reference electrical signal, and a module for controlling at least one element of the dual-frequency optical source with a signal obtained from the signal resulting from the comparison.