Experimental investigation on propulsion performance of GAP ablated by combined pulse laser

With the high removal efficiency of materials during laser-matter interaction, combined pulse laser (CPL) has the prospect of being used in laser ablation micro-propulsion. In this paper, the energetic glycidyl azide polymer (GAP) is irradiated by the CPL that combined by millisecond and nanosecond lasers. The ablation morphology and the plume images are analyzed to explain the characteristics of propulsion parameters. Compared to the impulse of 5.72 mu N & sdot;s for a single nanosecond pulse with 130 mJ, the ablation pit promotes the millisecond laser energy to be absorbed with a maximum result of 12.07 mu N & sdot;s in the NS-leading combination mode. A peak value of 7.85 mu N & sdot;s can be achieved in the NS-following mode due to the strong coupling process of the nanosecond laser and the thermally expanding target.