【摘要】 用1064nm激光辐照金属样品,通过测量金属物质烧蚀阈值附近冲击波的渡越时间的突变,确定了Cu、黄Cu、Al3种样品在干燥空气中和潮湿空气中的烧蚀阈值。干燥空气,Cu为1.0J/cm2,黄Cu为0.9J/cm2,Al为0.68J/cm2;潮湿空气中,Cu为1.0J/cm2;黄Cu为0.7J/cm2;Al为0.38J/cm2。结果表明,潮湿空气中的黄Cu和Al样品烧蚀阈值降低了,而Cu样品的烧蚀阈值没有变化;黄Cu和Al样品烧蚀阈值降低的程度也不同,黄Cu为22%,Al为44%。更多还原

【Abstract】 Laser beam deflection has been used to observe thermal and sound wave or shock wave generated near the ablation threshold.The laser ablation thresholds of different metal samples in dry and moist atmospheric conditions have been detected by using a continuous porbe laser beam parallel to the surface of samples.Ablation threshold is 1.0 J/cm~2 for pure Cu and 0.9 J/cm~2 for brass and 0.68 J/cm~2 for Al in dry environment,1.0 J/cm~2 for pure Cu and 0.7 J/cm~2 for brass and 0.38 J/cm~2 for Al in moist environment.A comparison of the thresholds of different samples in dry and moist atmospheric conditions is made.The experimental results indicated that moisture indeed causes the reduction of ablation threshold to different extent for the metal samples we investigated.Results show that,ablation threshold reduces by 22 % for brass and 44 % for Al and does not reduce for pure Cu.更多还原