Abstract:
A model describing the graphitization of CVD diamond under the action of femtosecond laser radiation is proposed. The model combines thermal and kinetic aspects, taking into account the phase transition of diamond into graphite upon reaching critical conditions (temperature or charge carrier density). A mathematical model of the temperature field for a laser source is presented taking into account the dependencies for enthalpy and polarization. A mathematical model of the diamond-graphite phase transition under laser radiation is developed within the framework of the charge carrier density equation. The governing equations were presented in finite-difference form and discretized using a five-point stencil on a uniform grid. The finite-difference equations were solved using the explicit Euler scheme. Numerical simulation of diamond graphitization allowed us to estimate the key features of the initial stage of the process.
Keywords:modeling, graphitization, thermodynamic model of graphitization, numerical methods, phase transition.