A combination of failures of interfacial delamination and layer cracking in REBCO multilayered conductors

Zhang, Houyuan; Gao, Peifeng; Wang, Xingzhe

doi:10.1016/j.engfracmech.2022.108785

Cited by 6 publications

(2 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As experimental results indicated that typical interface failures occurred in a REBCO CC in the form of cracks on the REBCO and/or buffer layers, or delamination at the interface between these two layers [9,16], the delamination interface was defined by the zero-thickness cohesive layer between REBCO and buffer layer as shown in figure 1. The bilinear CZM [30] was adopted for interface delamination simulations, which has been used to study the delamination behavior of REBCO CC tapes [26,29,31] and epoxy-impregnated windings [32][33][34] in the past. Due to the asymmetry of the REBCO CC in the thickness direction, delamination in a REBCO CC tape induced by transverse anvil pull involves mixed-mode (normal and shear modes) loading and thus mixed-mode CZM is implemented in the delamination models, as shown in figure 2.…”

Section: Mixed-mode Interface Bilinear Czmmentioning

confidence: 99%

Error analysis for determining transverse tensile delamination strength of REBCO coated conductors by anvil test: numerical simulation demonstrations

Gao,

Zhang,

Lin

et al. 2024

Supercond. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

RE-Ba-Cu-O (REBCO, where RE = Y, Gd, Sm, and other rare earth elements) coated conductor (CC) tapes exhibit considerable potential for application within the domains of high-energy physics and high-field science. Nevertheless, weak interfacial properties pose a significant obstacle, impeding the progress and practical implementation in high-field scenarios. The anvil tension method has been extensively employed for the assessment of transverse delamination strength of REBCO CC tapes. However, the outcomes derived from anvil tension exhibit severe dispersion, thereby impeding its efficacy in evaluating material performance. The underlying cause of this phenomenon remains unidentified. In this study, error analysis of anvil measurement method in determining the transverse tensile delamination strength (TTDS) of REBCO CC tapes was conducted based on finite element (FE) numerical simulations. A two-dimensional multilayer elastic-plastic delamination FE model with main layers of REBCO CC tapes, solder connecting layers and anvil materials were developed based on the bilinear cohesive zone model. The effects of anvil test conditions and the structural configuration of the conductor itself on the test results were discussed. Simulation results show that localized premature cracking of the interface due to stress concentration and plastic yielding of the CC tape around the loading boundary is the root reason for the discrepancy between the anvil test results and the true interfacial strength. Therefore, anvil test conditions (including top anvil dimensions, soldering conditions, loading eccentricity angle, and anvil material properties) as well as the structural configuration of the conductor itself (including edge initial crack length, edge encapsulation width, and stabilizer thickness) have a significant impact on anvil test-based TTDS results.

show abstract

Section: Mixed-mode Interface Bilinear Czmmentioning

confidence: 99%

Error analysis for determining transverse tensile delamination strength of REBCO coated conductors by anvil test: numerical simulation demonstrations

Gao,

Zhang,

Lin

et al. 2024

Supercond. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Another threat posed by microcracks is interlaminar failure (interfacial delamination). Zhang et al [24] investigated the initial edge cracks (∼0.1 mm) on the interfacial delamination behavior of (RE)BCO tapes by the finite element method. The results show that crack propagation in the (RE)BCO layer causes delamination failure at the interface between the (RE)BCO layer and its adjacent layers.…”

Section: Introductionmentioning

confidence: 99%

Numerical analysis of the mechanical and electrical properties of (RE)BCO tapes with multiple edge cracks

Gao

2023

Supercond. Sci. Technol.

View full text Add to dashboard Cite

One of the leading causes of critical current degradation in (RE)BCO tapes is the micro-cracks produced by mechanical slitting. These cracks are scattered near the edge of the tape and vary in length and angle. In this work, a tape model with multiple edge cracks is established. Under tensile loading, the effects of the Poisson ratio, crack length, crack angle, crack spacing, and geometric mutation between cracks on the stress intensity factor are investigated using the extended finite element method (XFEM). Tensile experiments were conducted at room temperature to investigate the crack propagation behavior of tapes with multiple edge cracks. The results show that the stress intensity factor obtained using XFEM is more informative than the analytical solution, which ignores the Poisson effect. The stress intensity factor is sensitive to crack length and angle variations and exhibits an evident jump characteristic when a geometric mutation occurs. The jump level strongly depends on the geometric difference. The jump location is the initiation site for crack propagation, which is consistent with the experiment results. The strain analysis of the tape implies that high-strain regions exist at the crack tip before the tensile strain reaches the irreversible strain limit. The critical strain of crack propagation is closely related to the form of crack distribution. It dominates the irreversible strain limit of critical current degradation, which facilitates understanding the early degradation of critical current. Finally, some engineering suggestions are given.

show abstract

Numerical simulation of the mechanical behavior of superconducting tape in conductor on round core cable using the cohesive zone model

Tang,

Peng,

Yong

2023

Appl. Math. Mech.-Engl. Ed.

View full text Add to dashboard Cite

A combination of failures of interfacial delamination and layer cracking in REBCO multilayered conductors

Cited by 6 publications

References 43 publications

Error analysis for determining transverse tensile delamination strength of REBCO coated conductors by anvil test: numerical simulation demonstrations

Error analysis for determining transverse tensile delamination strength of REBCO coated conductors by anvil test: numerical simulation demonstrations

Numerical analysis of the mechanical and electrical properties of (RE)BCO tapes with multiple edge cracks

Numerical simulation of the mechanical behavior of superconducting tape in conductor on round core cable using the cohesive zone model

Contact Info

Product

Resources

About