Variation regularity of metal magnetic memory signals with inspecting time-interval and location
- 140 Downloads
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 wordsnondestructive testing metal magnetic memory inspecting interval inspecting location
Unable to display preview. Download preview PDF.
- DOUBOV A. Screening of weld quality using the magnetic metal memory effect[J]. Welding in the World(UK), 1998, 41(3): 196–199.Google Scholar
- DOUBOV A A. Express method of weldments inspection using metal magnetic memory[C]// Proceedings of 7th European Conference on Non-destructive Testing. Copenhagen, Denmark, 1998: 1266–1273.Google Scholar
- DUBOV A. Principle features of metal magnetic memory method and inspection tools as compared to known magnetic NDT methods[J]. Canadian Institute for NDE Journal, 2006, 27(3): 16–20.Google Scholar
- REN Ji-lin, LIN Jun-ming, CHI Yong-bing, et al. Metal Magnetic Memory Technique[M]. Beijing: China Electric Power Press, 2000. (in Chinese)Google Scholar
- LI Lu-ming, HUANG Song-ling, WANG Lai-fu, et a1. Research on magnetic testing method of stress distribution[J]. Trans Nonferrous Met Soc China, 2002, 12(3): 388–391.Google Scholar
- LI Lu-ming, HUANG Song-ling, WANG Xiao-feng, et a1. A study of stress induced magnetic field abnormality[J]. Trans Nonferrous Met Soc China, 2003, 13(1): 6–9.Google Scholar
- YAMASAKI T, YAMAMOTO S, HIRAO M. Effect of applied stresses on magnetostriction of low carbon steel[J]. Non-Destructive Testing and Evaluation International, 1996, 29(5): 263–268.Google Scholar
- DOUBOV A A. About physical base of method of metal magnetic memory[C]// 8th ECNDT Proceedings Abstracts Book. Barcelona, Spain, 2002. 132.Google Scholar
- TIAN Xi-tang. Welded Structure[M]. Beijing: China Machine Press, 1982. 47–52. (in Chinese)Google Scholar