نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکتری، دانشگاه سمنان، سمنان، ایران
2 استادیار، دانشگاه سمنان، سمنان، ایران
3 دانشیار دانشگاه سمنان، سمنان، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Today, the interaction of laser beams with materials has a wide range of interests in daily, industrial, scientific, and medical applications. In the paper, the interaction of a single nanosecond pulse of a second harmonic Nd-YAG laser with gold metal is investigated to obtain a more comprehensive understanding of the basics of laser beam interaction with metals and to evaluate the appropriate conditions for laser radiation. The simulations were done by solving the quadratic equation of heat in three dimensions with the Generalized Finite Difference Time Domain (G-FDTD) method using Fortran programming language. Also, metal properties such as the thermal conductivity and specific heat capacity of gold are considered as a function of temperature in the model so that the results are closer to reality. The results indicate that the energy per pulse and linewidth of the laser pulse and also the spot size of the laser beam have a significant effect on the distribution of temperature on the surface and depth of the gold and also on the heat-affected zone (HAZ). Indeed, the maximum temperature is directly related to increases in energy per pulse. While it shows an inverse relationship between the time linewidth of the laser pulse and the spot size of the laser beam. Also, the time of maximum temperature has a delay compared to the peak of the laser pulse, and this delay time shows a direct and linear relationship with the linewidth of the laser pulse. In addition, the dependences of the gold melting threshold to characteristic parameters of the laser including laser spot size, laser linewidth, and laser fluences are studied in the paper to provide a general map for users to achieve melting of the gold by exposing the nanosecond pulse of second harmonic Nd-YAG laser.
کلیدواژهها [English]
)