Destructive mechanisms in laser induced forward transfer

Abstract

Laser Induced Forward Transfer (LIFT) is an additive direct-writing technique, in which a piece of material (ink) is transferred from a donor to a receiver surface, utilizing a laser impulse. In practice, the process of jet formation can suffer from irreproducibility. We identify two possible destructive mechanisms due to multiple optical breakdowns (originating from imperfections of the optical system) and rarefaction waves (originating from impurities), both with harmful consequences caused by cavitation. Based on experiments in a model system that allows for visualization and numerical simulations employing the boundary integral method, we reveal the underlying fluid dynamics of both mechanisms. Finally, to overcome the irreproducibility, we provide recommendations for the industrial use of LIFT.