In situ μ CT-scan Mechanical Tests: Fast 4D Mechanical Identification

Jailin, Clément; Bouterf, Amine; Poncelet, Martin; Roux, Stéphane

doi:10.1007/s11340-017-0305-z

Cited by 24 publications

(16 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under these conditions, the reference scan is performed when the sample is unloaded (or very modestly preloaded), and then radiographs are acquired on the fly without any inter-ruption of the test [110]. In such situations, Projection-based DVC (P-DVC) is utilized [124].…”

Section: In-situ Testsmentioning

confidence: 99%

Digital Volume Correlation: Review of Progress and Challenges

et al. 2018

Self Cite

View full text Add to dashboard Cite

3D imaging has become popular for analyzing material microstructures. When time lapse series of 3D pictures are acquired during a single experiment, it is possible to measure displacement fields via digital volume correlation (DVC), thereby leading to 4D results. Such ForewordThe present paper aims at reviewing the major developments in Digital Volume Correlation (DVC) over the past ten years. It follows the first review on DVC that was published in 2008 by its pioneer [11]. In the latter, the interested reader will find all the general principles associated with what is now called local DVC. They will not be recalled hereafter. In such approaches the region of interest is subdivided into small subvolumes that are independently registered. In addition to its wider use with local approaches, DVC has been extended to global approaches in which the displacement field is defined in a dense way over the region of interest. Kinematic bases using finite element discretizations have been selected. To further add mechanical content, elastic regularization has been introduced. Last, integrated approaches use kinematic fields that are constructed from finite element simulations with chosen constitutive equations. The material parameters (and/or boundary conditions) then become the quantities of interest.These various implementations assume different degrees of integration of mechanical knowledge about the analyzed experiment. First and foremost, DVC can be considered as a stand-alone technique, which has seen its field of applications grow over the last ten years. In this case the measured displacement fields and post-processed strain fields are reported. With the introduction of finite element based DVC, the measured displacement field is continuous. It is also a standalone technique. However, given the fact that it shares common kinematic bases with numerical simulations, it can be easily combined with the latter. One route is to require local satisfaction of equilibrium via mechanical regularization. Another route is to fully merge DVC analyses and numerical simulations via integrated approaches. Different examples will illustrate how these various integration steps can be tailored and what are the current challenges associated with various approaches.

show abstract

Section: In-situ Testsmentioning

confidence: 99%

Digital Volume Correlation: Review of Progress and Challenges

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is interesting to note that these Hessian matrices are exactly the same as static and fully defined P-DVC procedure, as presented e.g., in [34]. Indeed the assumption on the stationary amplitude allows one to treat this measurement as if it were static.…”

Section: Pgd Modal Analysismentioning

confidence: 93%

Measurement of 1–10 Hz 3D vibration modes with a CT-scanner

Jailin

Roux

2020

Adv. Model. and Simul. in Eng. Sci.

Self Cite

View full text Add to dashboard Cite

A new in situ vibration mode measurement method within a tomograph is proposed based on Projection-based Digital Volume Correlation techniques. Several projection angles are selected and a large number of radiographs of the vibrating sample are acquired at random instants with a small exposure time in order to 'freeze out' the displacement and avoid motion blurring. Based on an initial reconstruction acquired in a static configuration, the displacement field measurement is performed using a Proper Generalized Decomposition technique. All projections are analyzed as being due to a few vibration modes deforming the known reference volume. The different projection directions are related to each other assuming that the modal amplitude probability distribution functions are statistically similar. A synthetic test case, mock-up of a liver, is used to illustrate and validate the approach. In this case, 5 projection angles were chosen, 300 radiographs per angle, and the first three vibration modes could be recovered with a good accuracy.

show abstract

“…An alternative route consists in combining DVC and reconstruction steps [11]. With such approaches, the in situ test in no longer interrupted and the radiographs are acquired on the fly [12], thereby allowing mechanical tests to be performed in a few minutes in lab-scale tomographic equipments.…”

Section: Challengesmentioning

confidence: 99%