对激光加工连杆裂解槽工艺进行了研究，根据材料状态、能量平衡和孔形变化，将脉冲激光加工裂解槽孔过程分为起始、准稳定破坏及收尾3个阶段；对脉宽、波形、脉冲频率、切割速度等影响裂解槽槽根半径的因素进行了分析；设计了一种新的激光脉冲波形，以满足槽根尖锐度的要求。分析及实验结果表明：长脉冲宽度与切割速度的合理匹配是获得尖锐裂解槽的关键，当脉宽取1 ms，切割速度为10 mm/s时，获得了根部尖锐的裂解槽。对于要求深且尖锐的裂解槽，可增加频率转化为多个长脉冲加工；当频率增加到40 Hz，脉宽取0.5 ms，得到的裂解槽纵横比大且根部尖锐。裂解槽形貌对比表明，对于脉宽和频率进行优化，可在加工裂解槽孔的各个阶段合理地注入能量，获得高质量的裂解槽。

A laser cutting process for the fracture splitting notch of a connecting rod was researched in this paper.According to the material behaviors, energy balance and the changes of hole shapes, the process was divided into three stages, initial state, quasi-steady destruction and tail stage.The affects of pulse width, waveform, pulse frequency and cutting speed on the notch root radius were analyzed, and a new pulse waveform was designed to satisfy the request of notch root sharpness.Analysis and experimental results show that a long pulse width combined with a reasonable cutting speed is the key to obtain a sharp fracture splitting notch.When the pulse width is set to be 1 ms, cutting speed to be 10 mm/s, the sharp fracture splitting notch can be obtained.Furthermore, for a deeper and sharper notch, it can be transformed into many long pulse processing by increasing the frequency.When the frequency is increased to 40 Hz, pulse width to 0.5 ms, the fracture splitting notch with a larger aspect ratio and a sharp root can be obtained.By comparison of the morphologies for the fracture splitting notch,it indicates that proposed process can achieve the sharp fracture splitting notch with higher quality by injecting energy reasonably into each stage in laser processing.