Twohyphen;channel optical pyrometry of metals irradiated by picosecond laser pulses

摘要

We have used twohyphen;channel optical pyrometry to study the surface color temperature versus time profiles of aluminum and tungsten irradiated with 100 ps, 5 ns, and 60ndash;70 ns duration pulses of Ndhyphen;glass laser in the fluence range of 0.5ndash;15 J/cm2. We demonstrate that at fluences of several J/cm2the temperatures of both materials can rise above 5000 K. The maximum observed cooling rates are 5times;1010K/s, two orders of magnitude less than the theoretical estimation. The importance of these results for the laser annealing experiments on metals and alloys is discussed.