- 标题
- 摘要
- 关键词
- 实验方案
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Effects of channel alternating corrugation on a laser beam propagation in plasmas
摘要: The propagation of an intense laser beam in an alternating corrugated plasma channel, which has a wide region and a narrow region in one corrugated space period, is investigated. Compared with the usual corrugated plasma channel, it is found that there are many more resonance peaks and many more abundant beat-like wave phenomena for the laser beam in this extended channel. Moreover, the much narrower region in some special alternating corrugated channels can play the role like a plasma lens for some laser beams, i.e., it can obviously change the laser spot size from small (large) to large (small) amplitude when the laser passes through the narrow region. These results are well confirmed by the final numerical simulations of wave equation and particle-in-cell approach.
关键词: Laser beam,Conversion,Resonance,Corrugated plasma channel,Propagation characteristics,Beat-like wave
更新于2025-09-16 10:30:52
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A new acoustic emission on-line monitoring method of laser shock peening
摘要: Laser shock peening (LSP) is an advanced surface modification technology that can harden metallic materials by using plasma shock waves. It has significant technical advantages and has important application value in various fields like the aerospace, defense and military. In order to realize the large-scale industrial production of LSP, it is necessary to strengthen on-line monitoring of its working status. Acoustic emission (AE) is a dynamic non-destructive technique to evaluate the material performance change in real-time, which overcomes many shortcomings of traditional non-destructive testing methods and has been successfully applied to on-line monitoring of LSP. Generally the signal and characteristic parameters of AE are affected by sensor position, which is inconvenient to evaluate the quality of LSP in unified standard. The propagation characteristics of AE and the planar positioning function of AE were concerned in this work, the AE energy of material was obtained from detected waveforms and characteristic parameters of AE by calculation, which is helpful to realize the on-line monitoring of LSP.
关键词: AE energy,on-line monitoring,planar positioning,propagation characteristics,laser shock peening,acoustic emission
更新于2025-09-11 14:15:04