Friction-induced subsurface densification of glass at contact stress far below indentation damage threshold (Elsevier proof PDF)

Summary¶

This entry tracks an Elsevier author proof PDF for the Acta Materialia article (DOI 10.1016/j.actamat.2020.03.005) on friction-induced subsurface densification of borosilicate glass in liquid water, with ReaxFF molecular dynamics supporting the experimental story. The scientific claims are the same as on the version-of-record page 2020he-acta-materia-friction-induced-subsurface, which uses papers/He_Glass_densification_ActaMater_2020.pdf. In brief, the work shows that frictional shear can drive subsurface densification at a nominal Hertzian contact pressure near ~0.5 GPa in water—below pressures usually tied to indentation-induced densification. Experiments combine sub-Tg annealing volume recovery, nanoindentation, and alkaline dissolution on wear tracks, while MD illustrates how shear enables subsurface structural change when purely normal loading would remain elastic. The proof duplicate matters for corpus hygiene: some working trees may only hash He_Glass_densification_ActaMater_2020_proof.pdf, so this page keeps manifest rows, wikilinks, and retrieval chunks aligned with that blob while steering readers to the VOR for authoritative pagination and figure reproduction.

Methods¶

Same study as 2020he-acta-materia-friction-induced-subsurface: experiments (reciprocating tribology, sub-T\(_g\) annealing, nanoindentation, pH 13 dissolution) plus molecular dynamics in LAMMPS with ReaxFF on amorphous slab supercells (\(>10^3\) atoms), PBC in plane, NVT thermostat at K-level temperature, femtosecond timestep, ns-scale production duration; N/A — NPT barostat for typical shear NVT; Hertzian ~0.5 GPa in experiments for scale comparison. This proof PDF may differ cosmetically from the VOR; full tables: 2020he-acta-materia-friction-induced-subsurface.

Findings¶

Matches the published work: low-pressure frictional conditions can yield mechanochemical wear and densification signatures while suppressing some classic brittle subsurface cracking modes emphasized in higher-load indentation folklore; sub-Tg annealing supports volume recovery consistent with densified glass in the wear track; nanoindentation and dissolution show the track differs from untouched surface regions; ReaxFF trajectories support the qualitative picture that shear lowers the barrier to subsurface restructuring relative to purely normal loading at comparable nominal pressure. None of these statements should be re-sourced from the proof PDF alone—use 2020he-acta-materia-friction-induced-subsurface for quantitative tables and figure callouts.

Limitations¶

Proof PDFs may include editorial markup and differ from the typeset issue in pagination and figures. Prefer 2020he-acta-materia-friction-induced-subsurface for citation hygiene. Figure labels, supplement pointers, and final unit formatting should be taken from the version-of-record PDF when preparing external citations or reproducing plots.

Relevance to group¶

Operator duplicate; full curated narrative lives on 2020he-acta-materia-friction-induced-subsurface (He / Hahn / van Duin / Kim).

Citations and evidence anchors¶

DOI: 10.1016/j.actamat.2020.03.005 — proof: papers/He_Glass_densification_ActaMater_2020_proof.pdf; VOR: papers/He_Glass_densification_ActaMater_2020.pdf.

Canonical curated body: 2020he-acta-materia-friction-induced-subsurface.