”Finite-element” displacement fields analysis from digital images : application to Portevin-Le Châtelier bands
نویسندگان
چکیده
A new methodology is proposed to estimate displacement fields from pairs of images (reference and strained) that evaluates continuous displacement fields. This approach is specialized to a finite-element decomposition, therefore providing a natural interface with a numerical modeling of the mechanical behavior used for identification purposes. The method is illustrated with the analysis of Portevin-Le Châtelier bands in an aluminum alloy sample subjected to a tensile test. A significant progress with respect to classical digital image correlation techniques is observed in terms of spatial resolution and uncertainty. Correspondence to: François Hild, Email: [email protected], Fax: +33 1 47 40 22 40. Manuscript Click here to download Manuscript: plc_q4.tex
منابع مشابه
Time-resolved strain mapping measurements of individual Portevin–Le Chatelier deformation bands
A technique based on high-speed digital photography and image correlation for direct whole-field strain mapping of Portevin–Le Chatelier deformation bands is described. Results for a type B band show that the deformation band was formed within a few milliseconds and remained stationary as no motion of the band was detected. 2005 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
متن کاملFrom image analysis to damage constitutive law identification
Based on digital images of a tested sample, taken at different stages of loading, displacement fields are measured by using digital image correlation. The technique used here directly provides continuous displacement fields decomposed onto finite elements. From the latter, the equilibrium gap method allows one to estimate a scalar damage field over the same region of interest. Last, under the a...
متن کاملStress Field Analysis of V-Notches with Tip Cracks in a Polymer Material Using Digital Image Correlation
In this study, displacement field around v-notches of a poly methyl metha crylate (PMMA) specimen with tip cracks will be analyzed using digital image correlation technique. First intensity factor in combination with in-plane rigid body translations and rotation components will be determined by linear least squares fitting of the displacement field data to the corresponding relations among stre...
متن کاملNonlinear Finite Element Analysis of Bending of Straight Beams Using hp-Spectral Approximations
Displacement finite element models of various beam theories have been developed using traditional finite element interpolations (i.e., Hermite cubic or equi-spaced Lagrange functions). Various finite element models of beams differ from each other in the choice of the interpolation functions used for the transverse deflection w, total rotation φ and/or shear strain γxz, or in the integral form u...
متن کاملThermo-elastic analysis of a functionally graded thick sphere by differential quadrature method
Thermo-elastic analysis of a functionally graded hollow sphere is carried out and numerical solutions of displacement, stress and thermal fields are obtained using the Polynomial differential quadrature (PDQ) method. Material properties are assumed to be graded in the radial direction according to a power law function, ho...
متن کامل