Comparison of different techniques for the monitoring of the Lüders bands development
In C-Mn and some low alloyed steels, the plastic deformation begins by a macroscopic heterogeneous strain which materializes into the propagation of a strain band along a tensile sample with a uniform cross-section. This band is named Lüders, or Piobert-Lüders, band and it is considered by some authors as a plastic wave. This particular strain localization, which goes through the length of the sample, is explained by an avalanche phenomenon which enables step by step to unfix the dislocations from their Cottrells atmosphere. However, although its effects are well enough known, one knows much less its causes. In this paper, the travel of the Lüders band is monitored thanks to several techniques based on different physical principles: optical (speckle interferometry), thermal (infrared pyrometry) and acoustic (acoustic emission). The position of the band, its inclination, its propagation speed and the strain rate inside the band are the main points of comparison between each technique. They allow verifying some features about the propagation of the bands and giving some new assumptions about their formation and their development.
Luders Band Strain Localization Infrared Thermography (IRT) Electronic Speckle Pattern Interferometry (ESPI) Acoustic Emission (AE) Tensile Test
J.Petit D.Wagner N.Ranc G.Montay M.Fran(c)ois
LEME,EA4416,Université Paris Ouest,92410 Ville dAvray,France PIMM,CNRS,151 Bd de lH(o)pital,75013 Paris,France LASMIS,UMR CNRS 6279,University of Technology of Troyes,10010 Troyes,France
国际会议
北京
英文
1-13
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）