Understanding interfacial fracture behavior between microinterlocked soft layers using physics-based cohesive zone modeling

Navajit S. Baban, Ajymurat Orozaliev, Christopher J. Stubbs, Yong Ak Song

Research output: Contribution to journalArticlepeer-review

Abstract

We examine the underlying fracture mechanics of the human skin dermal-epidermal layer's microinterlocks using a physics-based cohesive zone finite-element model. Using microfabrication techniques, we fabricated highly dense arrays of spherical microstructures of radius ≈50μm without and with undercuts, which occur in an open spherical cavity whose centroid lies below the microstructure surface to create microinterlocks in polydimethylsiloxane layers. From experimental peel tests, we find that the maximum density microinterlocks without and with undercuts enable the respective ≈4-fold and ≈5-fold increase in adhesion strength as compared to the plain layers. Critical visualization of the single microinterlock fracture from the cohesive zone model reveals a contact interaction-based phenomena where the primary propagating crack is arrested and the secondary crack is initiated in the microinterlocked area. Strain energy energetics confirmed significantly lower strain energy dissipation for the microinterlock with the undercut as compared to its nonundercut counterpart. These phenomena are completely absent in a plain interface fracture where the fracture propagates catastrophically without any arrests. These events confirm the difference in the experimental results corroborated by the Cook-Gordon mechanism. The findings from the cohesive zone simulation provide deeper insights into soft microinterlock fracture mechanics that could prominently help in the rational designing of sutureless skin grafts and electronic skin.

Original languageEnglish (US)
Article number012801
JournalPhysical Review E
Volume102
Issue number1
DOIs
StatePublished - Jul 2020

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Understanding interfacial fracture behavior between microinterlocked soft layers using physics-based cohesive zone modeling'. Together they form a unique fingerprint.

Cite this