Materials processing by high-repetition-rate pulsed excimer and carbon dioxide lasers

A high-repetition-rate (HRR) carbon dioxide laser provided a 10-micron radiation source in the considered experiments. The pulse width of this laser can be changed in the range from 0.5 to 10 microseconds. In some experiments, a HRR excimer laser capable of producing 10-nsec pulses was employed. Nd:glass and ruby lasers have also been used. A study of melt dynamics was conducted to simulate various stages of a HRR regime of materials processing. Attention is given to melt motion under pulsed excitation, the combined irradiation by two laser pulses, and questions of deep penetration by a HRR laser beam. Aspects of laser-plasma alloying are also discussed, taking into account the experimental procedure, experimental results, a theoretical model of the process, and new ideas regarding the structure of metallic glasses.