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Variation regularity of metal magnetic memory signals with inspecting time-interval and location

  • Yan Chun-yan  (严春妍)Email author
  • Li Wu-shen  (李午申)
  • Di Xin-jie  (邸新杰)
  • Xue Zhen-kui  (薛振奎)
  • Bai Shi-wu  (白世武)
  • Liu Fang-ming  (刘方明)
Article

Abstract

Influences of inspecting time-interval and location on varying behavior of metal magnetic memory (MMM) signals of defects were studied. Different areas in two precracked weldments were inspected at different time-intervals by type TSC-1M-4 stress-concentration magnetic inspector to obtain MMM signals. Mechanisms of MMM signals varying behavior with inspecting time and space were analyzed and discussed respectively. It is found that MMM signals don’t change with inspecting time-interval, since stress field and magnetic leakage field maintain unchanged at any time after welding. On the other hand, MMM signals differ greatly for different inspecting locations, because stress field and magnetic leakage field are unevenly distributed in defective ferromagnetic materials.

Key words

nondestructive testing metal magnetic memory inspecting interval inspecting location 

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Copyright information

© Published by: Central South University Press, Sole distributor outside Mainland China: Springer 2007

Authors and Affiliations

  • Yan Chun-yan  (严春妍)
    • 1
    Email author
  • Li Wu-shen  (李午申)
    • 1
  • Di Xin-jie  (邸新杰)
    • 1
  • Xue Zhen-kui  (薛振奎)
    • 2
  • Bai Shi-wu  (白世武)
    • 2
  • Liu Fang-ming  (刘方明)
    • 2
  1. 1.School of Materials Science and EngineeringTianjin UniversityTianjinChina
  2. 2.Petroleum-Gas Pipeline Research Institute of ChinaLangfangChina

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