Plastic response of amorphous silicates, from atomistic simulations to experiments – A general constitutive relation

Molnár, Gergely; Kermouche, Guillaume

doi:10.1016/j.mechmat.2017.07.002

Cited by 16 publications

(25 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The implementation of sigmoidal instead of linear densification hardening has a small influence on the nanoindentation load displacement response (Figure A). This agrees well with Molnar's observation that small changes in the densification behavior exhibit only a negligible effect on the macroscopic LD response. The densification field beneath the residual impression (Figure ) can be visualized using the volumetric inelastic strain, which is given by the parameter PEQC4 in ABAQUS.…”

Section: Resultssupporting

confidence: 92%

“…The data presented in Figure shows the loading history of the stress states in a single element at indent center. The stress states of all elements below the indenter at maximum penetration depth can provide further useful insight into the plastic deformation . This corresponds to the loading situation in Figure (right side).…”

Section: Resultsmentioning

confidence: 98%

“…Molnar et al even found complex yield surface shape transformations which occurred upon densification . In direct comparison to this advanced model, the simpler approach by Kermouche et al, who approximated the yield surface of fused silica using an ellipse, still reproduces the load displacement behavior in Berkovich indentation experiments remarkably well; this model was successfully transferred to soda lime glass . In addition, it has been shown that the cap section of the modified Drucker‐Prager‐Cap (DPC) plasticity theory is able to replicate the elliptical yield surface for fused silica.…”

Section: Introductionmentioning

confidence: 97%

“…Several constitutive models 8,[26][27][28][29][30][31][32] have been developed to describe the anomalous plastic flow behavior of fused silica. First attempts considered volume-conservative plastic shear flow using von Mises plasticity.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Indentation densification of fused silica assessed by raman spectroscopy and constitutive finite element analysis

Bruns

Uesbeck²,

Fuhrmann

et al. 2020

J Am Ceram Soc

View full text Add to dashboard Cite

Inelastic deformation of anomalous glasses manifests in shear flow and densification of the glass network; the deformation behavior during indentation testing is linked strongly to both processes. In this paper, the indentation densification field of fused silica is investigated using depth‐resolved Raman spectroscopy and finite element simulations. Through affecting the size of the indent, the normal load and the Raman laser spot size determine the spatial sampling resolution, leading to a certain degree of structural averaging. For appropriate combinations of normal load (indent size) and laser spot diameter, a maximum densification of 18.4% was found at the indent center. The indentation behavior was modeled by extended Drucker‐Prager‐Cap (DPC) plasticity, assuming a sigmoidal hardening behavior of fused silica with a densification saturation of 21%. This procedure significantly improved the reproduction of the experimental densification field, yielding a maximum densification of 18.2% directly below the indenter tip. The degree of densification was found to be strongly linked to the hydrostatic pressure limit below the indenter in accordance to Johnson's expanding cavity model (J. Mech. Phys. Solids, 18 (1970) 115). Based on the good overlap between FEA and Raman, an alternative way to extract the empirical correlation factor m, which scales structural densification to Raman spectroscopic observations, is obtained. This approach does not require the use of intensive hydrostatic compaction experiments.

show abstract

Section: Resultssupporting

confidence: 92%

Section: Resultsmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Indentation densification of fused silica assessed by raman spectroscopy and constitutive finite element analysis

Bruns

Uesbeck²,

Fuhrmann

et al. 2020

J Am Ceram Soc

View full text Add to dashboard Cite

show abstract

“…In this connection, simulations of glass network cavitation development using MD under various types of loading and finite element analysis of indentation stress fields incorporating the various (trial values of) yield strengths and matching computed deformations to observed indentation contours present challenging opportunities. In this connection, the work of Molnár et al appears to be in the right direction.…”

Section: What Is Yet To Be Learned To Obtain Stronger Glass Products?mentioning

confidence: 81%

Stronger glass products: Lessons learned and yet to be learned

Varshneya

2018

Int J of Appl Glass Sci

View full text Add to dashboard Cite

Potential for obtaining stronger glass products is discussed. Flaws, mostly forming‐ and handling‐generated and accelerated crack growth due to surrounding environment appear to give a strength distribution which is usually a factor of 500‐1000 less than the estimated theoretical strength. Contrary to traditional teachings emphasizing glass strength to be an extrinsic behavior, it is suggested that the atomic network topology determines the shear and hydrostatic yield strengths which are a precursor to the nucleation and growth of network cavitation, in turn, leading to generation of flaws and stress‐assisted growth starting from glass product‐forming processes. Hence, for stronger glass products, research is needed to develop fundamental understanding of the interrelationship between network topology, yield strengths, flaw cavitation and growth in molten glass as well as in solid glass as a function of glass composition and the complex stress fields around indents and impacts.

show abstract

Mechanical Properties of Glass

Guin

Guéguen

2019

Springer Handbooks

View full text Add to dashboard Cite

Plastic response of amorphous silicates, from atomistic simulations to experiments – A general constitutive relation

Cited by 16 publications

References 40 publications

Indentation densification of fused silica assessed by raman spectroscopy and constitutive finite element analysis

Indentation densification of fused silica assessed by raman spectroscopy and constitutive finite element analysis

Stronger glass products: Lessons learned and yet to be learned

Mechanical Properties of Glass

Contact Info

Product

Resources

About