On the propagation and pulsation of Portevin-Le Chatelier deformation bands: An experimental study with digital speckle pattern metrology

• Published in: International journal of plasticity 2005-11, Vol.21 (11), p.2150-2173
• Main Authors: Zhang, Qingchuan, Jiang, Zhenyu, Jiang, Huifeng, Chen, Zhongjia, Wu, Xiaoping
• Format: Article
• Language: English
• Subjects: A.Dynamics; Aluminum base alloys; B.Elastic–viscoplastic material; B.Metallic material; Banded structure; Bands; C.Optical interferometry; C.Optical microscopy; Deformation; Digital; Elastic deformation; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); Metrology; Physics; Product life cycle; Solid mechanics; Speckle patterns; Static elasticity (thermoelasticity...); Structural and continuum mechanics
• ISSN: 0749-6419; 1879-2154
• DOI: 10.1016/j.ijplas.2005.03.017

The Portevin-Le Chatelier (PLC) effect is closely associated with inhomogeneous deformation, which is characterized by the band of strain localization. In this work, the spatio-temporal dynamics of the Portevin-Le Chatelier deformation bands are investigated by a novel digital speckle pattern metrology technique consisting of digital speckle pattern interferometry (DSPI) and digital speckle correlation (DSC). A series of tension process of a commercial aluminum alloy (A2017) under different imposed strain rates in a range from 10 −6 to 10 −3 s −1 are monitored in real time with this technique. The formation of the PLC band, the evolution of the band structure and the propagation of the band are visualized and followed by fringe patterns. The distribution of the deformation in the specimen containing the band is measured precisely. It is shown that even for a tensile test, an elastic shrinkage deformation, which is caused by the avalanche-like shearing deformation within the band, occurs outside the band.