An advanced methodology for the development of highly accurate two temperature models (TTMs) to describe the material irradiation by an ultrashort laser

Abstract

Ultrashort lasers are an evolving field in both the researching and industrial world, mainly due to their ability to give very small Heat Affected Zones (HAZ) during the irradiation of a material, making them efficient for micro- and nanostructuring. Two Temperature Models (TTMs) are widely used in literature to simulate the irradiation of a material by an ultrashort laser, however, still now, they have some significant limitations, such as boundary conditions and mesh size dependency and low accuracy in predicting ablation depth and crater diameter. The novelty of the current paper is that it proposes an advanced methodology for the development of heat transfer-only TTMs, with boundary conditions and mesh size independency, that are able to predict ablation depth and crater diameter with very high accuracy, as they take into consideration phenomena such as spallation, explosive boiling and Kerr effect. As an example, this methodology has been applied on the ultrashort laser irradiation of Au.