Heating and Fusion of a Tungsten Micro Sphere Using Powerful Laser Irradiation

Abstract

The intense laser irradiation of a micro/nano size W sphere sample is considered in the present paper. Like numerical example, we choose a sphere with a radius of 1 µm. The present article’s point consists of approximating that the target’s temperature homogenization time is of the same order of magnitude as the first laser pulse duration. Our model is valid in the radius limits: 10 nm to 10 µm. We consider like heating source a laser beam with YAG/Nd:YAG/Cr4+:YAG composite crystal. The nature of the interaction between a laser beam and small dimension tungsten (W) sample is of great importance for both theoretical and experimental perspectives. In principle, we have three stages: i) laser- W bulk interaction; ii) plasma formation, heating, and iii) adiabatic expansion. In the present paper, we will focus on the first two stages of laser pulse interval.