Equivalence analysis of thermal response of materials irradiated with constant power and ultra-long pulsed laser

Ultra-long pulsed lasers are increasingly utilized as heat sources in material processing. Understanding the thermal response of materials under such irradiation is of great significance. This paper presents an equivalent method for determining the maximum temperature of materials subjected to both constant power and ultra-long pulsed laser irradiation. We conducted a theoretical analysis employing critical temperature values alongside numerical simulations that account for the heat transfer properties of various materials. These analyses aimed to estimate the peak temperature experienced by materials under the influence of both constant power and ultra-long pulsed laser treatments. To validate our findings, we carried out a thermal response equivalent verification experiment focused on a thermally-thick material. The results demonstrate that the peak temperatures achieved under both irradiation modes are approximately equivalent. Furthermore, the time required to reach maximum temperature shows good agreement, with a deviation of less than 17%. These findings enhance our understanding of thermal responses in material processing and may inform future applications of ultra-long pulsed lasers.