飞秒激光精微烧蚀是一种新型的精密加工方法。本文研究了飞秒激光烧蚀面齿轮材料18Cr2Ni4WA的电子亚系统和晶格亚系统的能量耦合作用，建立了双温模型，采用有限差分法分析了脉冲宽度、平均功率对电子温度和晶格温度的影响规律。结果表明：当电子与晶格达到热平衡，且电子温度和晶格温度超过材料的熔点时，齿面产生烧蚀；当电子和晶格的温度均高于材料的沸点和相爆炸温度时，主要通过相爆炸实现材料的去除；材料烧蚀深度一般为40 nm左右，避免了热效应对表层质量的影响。采用飞秒激光微加工系统进行实验研究，得出了能量密度呈高斯分布的飞秒激光烧蚀材料18Cr2Ni4WA的单脉冲烧蚀阈值为0.29 J/cm²；分析了平均功率和脉冲数对烧蚀形貌的影响。通过研究飞秒激光精微加工材料18Cr2Ni4WA的烧蚀特性，为提高面齿轮的加工质量提供了技术基础。

Femtosecond laser micro-ablation is a new high-precision processing method. In this study, the ablation characteristics of a face gear material (18Cr2Ni4WA steel) were studied. The energy coupling effect of the electronic and lattice subsystems of the ablated 18Cr2Ni4WA steel was investigated. In addition, a two-temperature model was established, and the effects of pulse width and average power on electron and lattice temperature were simulated using the finite difference method. Results reveal that when thermal equilibrium between electron and lattice is reached and the electron and lattice temperatures exceed the melting point of the material, the tooth surface is ablated; furthermore, when the electron and lattice temperatures are higher than the material boiling and phase explosion temperature, the material removal is mainly achieved by phase explosion. The material ablation depth is generally taken as ~40 nm to prevent the thermal effects on surface quality. The single-pulse ablation threshold of the 18Cr2Ni4WA steel ablated by a Gaussian distributed femtosecond laser using the femtosecond laser microprocessing system was 0.29 J/cm². The effects of average power and pulse number on the ablative morphology of the material were analyzed. The ablation characteristics of the 18Cr2Ni4WA steel microprocessed by a femtosecond laser in this study provide a technical basis for improving the processing quality of face gears.