Effectiveness of RP and CW Lasers for Target Damages

Physical Sciences Inc. (PSI) proposes an experimental and analysis program to determine the relative advantages or limitations of two different high-energy laser waveforms for inflicting lethal damage to metal aerospace targets. Repetitively pulsed (RP)and continuous wave (CW) waveforms will be used to irradiate steel, a typical tactical target material. Metal melting rates will be measured and melt removal phenomena observed. The melt-through times will be compared to predictions from PSI thermalresponse models for RP and CW material heating. Any advantages of vaporization-assisted melt removal for the RP waveform will be quantified. A fundamental understanding of the lethality of RP and CW lasers against military targets is important because ithelps to guide the development of the most effective high power laser technology. For example, in RP laser development understanding effects on materials could guide the technology in issues such as the most effective pulse lengths or pulse repetitionfrequencies. A better physical understanding of RP and CW interaction phenomenology could also provide guidance to the commercial laser market with optimized choices of laser waveforms ideally suited to cutting, machining, drilling, and welding ofmaterials.