title: Laser-Induced Spallation of Microsphere Monolayers.
abstract: The detachment of a semiordered monolayer of polystyrene microspheres adhered to an aluminum-coated glass substrate is studied using a laser-induced spallation technique. The microsphere-substrate adhesion force is estimated from substrate surface displacement measurements obtained using optical interferometry, and a rigid-body model that accounts for the inertia of the microspheres. The estimated adhesion force is compared with estimates obtained using an adhesive contact model together with interferometric measurements of the out-of-plane microsphere contact resonance, and with estimated work of adhesion values for the polystyrene-aluminum interface. Scanning electron microscope images of detached monolayer regions reveal a unique morphology, namely, partially detached monolayer flakes composed of single hexagonal close packed crystalline domains. This work contributes to the fields of microsphere adhesion and contact dynamics, and demonstrates a unique monolayer delamination morphology.
authors.affiliation: Department of Mechanical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Morgan
authors.initials: M
authors.lastname: Hiraiwa
authors.affiliation: Department of Mechanical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Melicent
authors.initials: M
authors.lastname: Stossel
authors.affiliation: Department of Mechanical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Amey
authors.initials: A
authors.lastname: Khanolkar
authors.affiliation: Department of Mechanical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Junlan
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Mechanical Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Boechler