研究了激光诱导放电(LGD)材料表面离散处理的机理和加工方法。在机理研究中发现激光诱导在大尺度上(放电点间隔)和小尺度上(放电点内部)都抑制了放电的随机性,实现了放电点位置的设定,增加了强化深度,提高了放电点的一致性。在LGD表面毛化研究中,发现随着峰值电流的升高,毛化坑凸起高度和毛化表面粗糙度(SRa)随之增大,毛化坑凸起的硬度达到1000 HV。在LGD表面强化研究中,发现通过控制放电电流和脉冲宽度能够获得不同径深比的强化点横截面形貌。在长脉冲宽度下强化点的径深比相似,高电流下的强化点直径更大,强化层更深,低电流则相反。在短脉冲宽度下强化点的深度相似,而高电流的径深比更大,低电流则相反。

The mechanism and method of laser-guided discharge (LGD) to discrete surface processing are studied. In the study of LGD mechanism,it is found that laser guiding controlles the randomicity of processing by common arc discharge in two sides,including a big scale (spacing of discharge areas) and a small scale (inside of discharge area). The position of discharge areas are controlled by the laser focus according to the design. The deepness of discharge areas are increased. The consistency of discharge areas is improved. In the study of surface texturing by LGD,the highness of rim of textured crater and the SRa of textured surface are increased with the augment of peak current. The hardness of rim of textured craters is about 1000 HV. In the study of surface strengthening by LGD,the cross-section shapes of strengthened areas are controlled with the peak current and pulse width. In long pulse-width of discharge,the ratios of diameter to deepness of strengthened areas are similar. The diameters of strengthened areas with high peak current are bigger than those with low peak current. The deepness of strengthened areas with high peak current are deeper than those with low peak current. In short pulse-width of discharge,the deepness of strengthened areas are similar. The ratios of diameter to deepness of strengthened areas with high current are bigger than those with low peak current.