Damage evolution analysis of SRM under compression using X-ray tomography and numerical simulation

Carbon/Phenolic (C/P), a typical anisotropic material, is an important component of aerospace and often used to protect the thermodynamic effects of strong X-ray radiation. In this paper, we establish the anisotropic elastic-plastic constitutive model, which is embedded in the in-house code “RAMA” to simulate a two-dimensional thermal shock wave induced by X-ray. Then, we compare the numerical simulation results with the thermal shock wave stress generated by the same strong current electron beam via experiment to verify the correctness of the numerical simulation. Subsequently, we discuss and analyze the rules of thermal shock wave propagation in C/P material by further numerical simulation. The results reveal that the thermal shock wave represents different shapes and mechanisms by the radiation of 1 keV and 3 keV X-rays. The vaporization recoil phenomenon appears as a compression wave under 1 keV X-ray irradiation, and X-ray penetration is caused by thermal deformation under 3 keV X-ray irradiation. The thermal shock wave propagation exhibits two-dimensional characteristics, the energy deposition of 1 keV and 3 keV both decays exponentially, the energy deposition of 1 keV-peak soft X-ray is high, and the deposition depth is shallow, while the energy deposition of 3 keV-peak hard X-ray is low, and the deposition depth is deep. RAMA can successfully realize two-dimensional orthotropic elastoplastic constitutive relation, the corresponding program was designed and checked, and the calculation results for inspection are consistent with the theory. This study has great significance in the evaluation of anisotropic material protection under the radiation of intense X-rays.

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Numerical simulation of the spectrum of X-ray natural circular dichroism in the CsCuCl3 crystal

Journal of Surface Investigation X-ray Synchrotron and Neutron Techniques ◽

10.1134/s1027451008040149 ◽

2008 ◽

Vol 2 (4) ◽

pp. 573-576 ◽

Cited By ~ 1

Author(s):

K. A. Kozlovskaya ◽

E. N. Ovchinnikova ◽

V. E. Dmitrienko ◽

A. Rogalev

Keyword(s):

Numerical Simulation ◽

Circular Dichroism ◽

X Ray ◽

Circular Dichroïsm

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Damage evolution and failure in a titanium alloy: Revealed by 3D in situ X-ray tomography

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.161689 ◽

2022 ◽

Vol 890 ◽

pp. 161689

Author(s):

Ning Dang ◽

Xuekun Luo ◽

Tao Suo ◽

Qingbo Dou ◽

Chaoli Ma ◽

...

Keyword(s):

Titanium Alloy ◽

Damage Evolution ◽

X Ray

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Direct Numerical Simulation of Pore-Scale Trapping Events During Capillary-Dominated Two-Phase Flow in Porous Media

Transport in Porous Media ◽

10.1007/s11242-021-01619-w ◽

2021 ◽

Author(s):

Mosayeb Shams ◽

Kamaljit Singh ◽

Branko Bijeljic ◽

Martin J. Blunt

Keyword(s):

Numerical Simulation ◽

Porous Media ◽

Direct Numerical Simulation ◽

Complex Geometry ◽

Flow In Porous Media ◽

Pore Scale ◽

Contact Lines ◽

Two Phase ◽

X Ray ◽

Aspect Ratios

AbstractThis study focuses on direct numerical simulation of imbibition, displacement of the non-wetting phase by the wetting phase, through water-wet carbonate rocks. We simulate multiphase flow in a limestone and compare our results with high-resolution synchrotron X-ray images of displacement previously published in the literature by Singh et al. (Sci Rep 7:5192, 2017). We use the results to interpret the observed displacement events that cannot be described using conventional metrics such as pore-to-throat aspect ratio. We show that the complex geometry of porous media can dictate a curvature balance that prevents snap-off from happening in spite of favourable large aspect ratios. We also show that pinned fluid-fluid-solid contact lines can lead to snap-off of small ganglia on pore walls; we propose that this pinning is caused by sub-resolution roughness on scales of less than a micron. Our numerical results show that even in water-wet porous media, we need to allow pinned contacts in place to reproduce experimental results.

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In Vivo X-ray Computed Tomography Investigations of Crack Damage Evolution of Cemented Waste Rock Backfills (CWRB) under Uniaxial Deformation

Minerals ◽

10.3390/min8110539 ◽

2018 ◽

Vol 8 (11) ◽

pp. 539 ◽

Cited By ~ 5

Author(s):

Yu Wang ◽

Changhong Li ◽

Zhiqiang Hou ◽

Xuefeng Yi ◽

Xiaoming Wei

Keyword(s):

Computed Tomography ◽

Damage Evolution ◽

Waste Rock ◽

Crack Identification ◽

Mining Operations ◽

Cracking Behavior ◽

Value Analysis ◽

X Ray ◽

Waste Rocks ◽

X Ray Computed

Cemented waste rock backfill (CWRB), which is a mixture of tailings, waste rock, cement, and water, is subjected to combination actions in underground mining operations and has been widely used in deep resource mining. While the strength requirement and macroscopic deformation behaviors of CWRB have been well studied, the mesoscopic damage evolution mechanisms are still not well understood. In this work, a CWRB sample with a waste rock proportion of 30% was studied with a uniaxial compression test under tomographic monitoring, using a 450 kV industrial X-ray computed tomography (CT). Clear CT images, CT value analysis, crack identification, and extraction reveal that CWRB damage evolution is extremely inhomogeneous and affected by the waste rock size, shape, and distribution. Furthermore, the crack initiation, propagation, and coalescence behaviors are limited to the existing waste rocks. When deformation grows to a certain extent, the cracks demonstrate an interlocking phenomenon and their propagation paths are affected by the waste rocks, which may improve the ability to resist compressive deformation. Volumetric dilatancy caused by the damage and cracking behavior has closed a link with the meso-structural changes, which are controlled by the interactions between the waste rocks and the cemented tailing paste.

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