长脉宽激光切割聚晶立方氮化硼工艺研究

为了获得聚晶立方氮化硼（PCBN）最优的激光切割质量和切割效率，依据烧蚀直径和入射激光脉冲能量的函数关系，得出PCBN烧蚀阈值为1.796J/cm2。采用Nd:YAG激光器对型号为BN250的PCBN进行切割试验，分析了切割速率、激光功率以及脉冲频率对切割质量的影响规律。通过切缝的显微观测对比，总结出不同激光工艺参量下PCBN缝宽的变化趋势。结果表明，对于脉宽为100μs的激光，当激光功率为28W、脉冲频率为60Hz、切割速率为20mm/min时，能够获得PCBN激光切割的最优切缝和较高的切割效率。该工艺方法和数据的建立，对今后PCBN或其它超硬材料的激光加工有着重要参考价值。

Technological study on long pulse laser cutting of polycrystalline cubic boron nitride

In order to obtain the optimal laser cutting quality and efficiency of polycrystalline cubic boron nitride(PCBN),the ablation threshold of PCBN material was obtained as 1.796J/cm2,based on the function relationship between the ablation diameter and laser energy.Cutting experiments of model BN250 PCBN with Nd:YAG laser were carried out.The effects of cutting speed,laser power and pulse repetition rate on cutting quality were analyzed.The changing trend of slit width of PCBN under different laser parameters was summarized by contrasting the microscopic observation.The results show that,the best quality of slit and the higher cutting efficiency can be obtained at the condition of laser power 28W,pulse repetition rate 60Hz,and cutting speed 20mm/min,by laser pulse with pulse duration 100μs.The method and process data have an important reference value for laser processing of PCBN or other superhard materials.