The influenceof plasma plume in Laser milling for mould manufacturing

The paper refers to the modeling of the plasma plume influence on the shape of the crater ob-tained by means of nanosecond pulsed laser milling. A transient model of the physical state of the plasma plume is developed according to the laser parameters. Two empirical coefficients are pro-posed in the model in order to evaluate the plasma plume self-emission energy lost towards the en-vironment and the energy spread from the plasma towards the target surface. These two coefficients, directly correlated to the depth and to the width of the crater, can be ex-perimentally determined, due to the difficulty of their analytical quantification, and they can be used for tuning a complete plasma plume software package for laser milling simulation named LAS (La-ser Ablation Simulator) already developed by the authors. In this paper their influence on the crater shape will be proved by means of several simulation runs.