Journal ArticleDOI
Investigation on mechanism of plastic deformation by digital speckle pattern interferometry
X. L. Gong,S. Toyooka +1 more
TLDR
An experimental scheme of digital speckle pattern interferometry using two electromagnetic shutters and a three-frame color image board is presented to measure two in-plane components of incremental displacement field of diffuse objects as mentioned in this paper.Abstract:
An experimental scheme of digital speckle pattern interferometry using two electromagnetic shutters and a three-frame color image board is presented to measure two in-plane components of incremental displacement field of diffuse objects. The deformation of the entire process from initial elastic deformation to fracture can be observed by using a Magneto Optical (MO) disk that has enough memory to record the image data of the entire process. By this system, some tensile experiments are achieved to investigate the mechanism of plastic deformation. The experimental results show that plastic deformation of tensile deformation is nonuniform. The material deforms in the distribution of domains. In the domains, the main deformation is uniform shear and rotation. At the boundary of the domains, the deformation is very large normal strain. With load, both the range and mode of domains are changing. At the end of plastic deformation, only two domains become dominant, and fracture happens at the boundary of the two domains.read more
Citations
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Journal ArticleDOI
On the propagation and pulsation of Portevin-Le Chatelier deformation bands: An experimental study with digital speckle pattern metrology
TL;DR: In this article, the spatio-temporal dynamics of the Portevin-Le Chatelier deformation bands are investigated by a novel digital speckle pattern metrology technique consisting of DSPI and DSC.
Journal ArticleDOI
Review of electronic speckle pattern interferometry (ESPI) for three dimensional displacement measurement
TL;DR: A review of the recent developments in ESPI systems for 3D displacement and strain measurement can be found in this article, where the basic theory, a brief derivation and different optical layouts are presented.
Journal ArticleDOI
Synergetic principles of physical mesomechanics
TL;DR: In this paper, a synergetic methodology of physical mesomechanics is developed to account for and substantiate well-known plastic-deformation and fracture mechanisms in solids under various loading conditions.
Journal ArticleDOI
Strain rate measurement by Electronic Speckle Pattern Interferometry: A new look at the strain localization onset
Bruno Guelorget,Manuel François,Cristián Vial-Edwards,Guillaume Montay,Laurent Daniel,Jian Lu +5 more
TL;DR: In this article, the authors used ESPI for tensile testing of semi-hard copper sheets in order tomeasure the strain rate and showed a very good accuracy of the total strain and strain rate measurements, which showed that a localization phenomenon occurs before the classic Considine's criterion (d F = 0) for the diffuse neck initiation.
Book ChapterDOI
Smoothing Measured Displacements and Computing Strains Utilizing Finite Element Method
Satoru Yoneyama,S. Kobayashi +1 more
TL;DR: In this paper, a method for smoothing measured displacements and computing strains utilizing a finite element method is proposed, where the displacement distribution is obtained by fitting the interpolation functions of finite elements to measured displacement values using the method of least squares.
References
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Journal ArticleDOI
Thickness and grain size dependence of limit strains in sheet metal stretching
K. Yamaguchi,P.B. Mellor +1 more
TL;DR: In this paper, a theoretical analysis of thickness and grain size dependence of the limit strain in isotropic sheet metals under biaxial tension is presented, where sheet surfaces are assumed to consist of asperities which increase proportionally with the equivalent strain and the grain diameter of the material.
Journal ArticleDOI
Determination of plastic strains at notches by image-proceessing methods
TL;DR: In this article, an image-processing method was developed to quantitatively extract the level of plastic deformation in metal specimens made of 304 stainless steel under remote tensile loading, and the effective strain distribution around the notch tip was obtained and compared with the finite-element results.
Journal ArticleDOI
Time-Division Observation of Plastic Deformation Process Using Digital Speckle Pattern Interferometry
Suprapedi,Satoru Toyooka +1 more
TL;DR: In this article, a tensile test of an aluminum plate exhibited dynamic movements of successive fringe patterns which were very complicated, suggesting that plastic deformation propagates nonlinearly in the specimen by repetition of energy relaxation processes and concentration processes.
Journal ArticleDOI
Digital speckle pattern interferometry for observing the entire process of plastic deformation of a solid object
Satoru Toyooka,Xinglong Gong +1 more
TL;DR: In this article, a new scheme of digital speckle pattern interferometry (DSPI) for observing the entire process of dynamic deformation from the beginning of elastic deformation to the end of plastic deformation at fracture is proposed.
Related Papers (5)
Digital speckle pattern interferometry for observing the entire process of plastic deformation of a solid object
Satoru Toyooka,Xinglong Gong +1 more
Time-Division Observation of Plastic Deformation Process Using Digital Speckle Pattern Interferometry
Suprapedi,Satoru Toyooka +1 more