飞秒激光旋切不锈钢微孔实验研究  

Experimental study on stainless steel micro-hole trepanned by femtosecond laser

作　　者：范楠楠[1,2] 夏振东[1,2] 孙小燕[1,2] 胡友旺[1,2] 

机构地区：[1]中南大学机电工程学院,湖南长沙4100831 [2]中南大学高性能复杂制造国家重点实验室,湖南长沙410083

出　　处：《激光与红外》2016年第10期1200-1205,共6页Laser & Infrared

基　　金：国家973项目(No.2011CB013000);国家自然科学基金项目(No.91323301;51475481;51475482);教育部新世纪优秀人才支持计划(No.NCET-12-0548)资助

摘　　要：为了解决飞秒激光高脉冲能量冲击打孔中时存在微裂纹等问题,提出了飞秒激光旋切加工方法。本文利用脉宽为120 fs的飞秒激光,选择0.5 mm厚度的304不锈钢进行旋切打孔实验。实验研究了激光旋切加工中离焦量和光楔的相对偏转角对孔直径的影响,以及激光离焦量对微孔锥度的影响。结果表明,随着离焦量的增大,孔径增大,同时锥度会减小后增加,当离焦量为0时,锥度最小为3.5°;微孔直径随之双光楔相对转角的增大而增大。此外实验发现冲击打孔孔壁出现微裂纹而旋切微孔的孔壁出现了纳米周期性条纹。In order to solve the problems of microcracks in high pulse energy femtosecond laser drilling,a trepanningmethod with femtosecond laser was proposed. The femtosecond laser with pulse width of 120 fs was used to trepan 304stainless steel with 0. 5 mm thickness. The effect of defocusing amount and relative deflection angle of double wedgeon the micro-hole diameter and the effect of defocusing amount on the micro-hole conicity are studied by the experiments.The results show that the diameters of micro-holes increases with the increasing of the defocusing amount,butthe conicity first decreases and then increases. When the defocusing amount is zero, the minimum conicity is 3.5°. Micro-hole diameter increases with relative deflection angle increase of double wedge. Nanometer periodic stripes arefound on the sidewalls of micro-holes trepanned by femtosecond laser,while there are microcracks on the sidewalls ofmicro-holes through percussion drilling.

关 键 词：飞秒激光 旋切打孔 304不锈钢 

分 类 号：TN249[电子电信—物理电子学]