Analysis of energy occupying ratio of Coulomb explosion and thermal effect in picosecond pulse laser processing

Molten material recasting may occur in ten picosecond laser processing although ultrashort-pulse processing is a kind of cold working method. It is also proved that experimental results do not fit expected processing results well in ten picosecond laser processing. What is more, some cracks on the surface of workpiece processed in ten picosecond laser can be observed. Aimed at above-mentioned facts processing in ten picosecond laser, a new hybrid model is raised. In this model, not only Coulomb explosion which is known to us but also thermal effect occurs in ten picosecond laser processing. Experiment method is used for analyzing the energy ratio of the two parts (Coulomb explosion and thermal effect). With OPENFOAM simulation software, the radius, topography and crack location of slots processed in different energy density are simulated. Finally, a comparison between simulation result and experimental result proves that this hybrid model is high degree of applicability and accuracy.