Modeling of Thermoelastic Stress Wave in Laser-Assisted Cell Direct Writing

Abstract

Laser-assisted cell direct-write technique has been a promising biomaterial direct-write method. For safe and reproducible cell direct writing, cell injury due to process-induced external stress must be understood in addition to biological property research. The objective of this study is to model the thermoelastic stress wave propagation inside the coating in laser-assisted cell direct writing when vaporization and/or optical breakdown of coating materials is/are not available. It is found that a bipolar pressure pair, with peak magnitudes on the order of 1 MPa or higher, has been developed within a finite thin coating medium. Shorter duration laser pulses lead to higher thermoelastic stresses. This study will help to understand the photomechanical stress and its relevance with biomaterial damage in laser-assisted cell direct writing.