KDP crystal is the primary nonlinear crystal for making core components of inertial confinement fusion and laser frequency doublings. However, as a soft-brittle material, KDP crystal is difficult to machine due to its easy deliquescence, high brittleness, and sensitive to high temperature. A theoretical model of temperature field during fly-cutting of KDP crystals assisted by coolant lubrication was established based on cutting-heat generation theory and thermal transmission theory. This model considered the thermal exchange between the air and work material, the thermal exchange between the fluid and work material, and anisotropy of KDP crystals. The predicted results of the model indicated that oil coolant could effectively increase the thermal diffusivity and decrease the friction coefficient between cutting tools and work materials, thus decreasing the cutting temperature during the fly-cutting process. The highest cutting temperature in coolant lubrication cutting decrease by 9.42–36.70% compared with that in dry cutting. The fly-cutting experiments of KDP crystals assisted by coolant lubrication were performed to verify the model, which indicated that experimental results agreed well with predicted temperatures and the average error of the highest temperature was approximately 7.78%. Both simulated and experimental results indicated that increasing feed speed and cutting depth or decreasing the cutting speed would result in the obvious increase of the highest cutting temperature.

KDP晶体是制造惯性约束聚变和激光倍频核心部件的主要非线性晶体。然而，KDP晶体作为软脆材料，易潮解、脆性大、对高温敏感，加工难度大。基于切削发热理论和传热理论，建立了冷却液润滑辅助下KDP晶体飞切过程中温度场的理论模型。该模型考虑了空气与工作材料之间的热交换、流体与工作材料之间的热交换以及 KDP 晶体的各向异性。模型的预测结果表明，油冷却剂可以有效地提高热扩散率，降低刀具与被加工材料之间的摩擦系数，从而降低飞切过程中的切削温度。冷却液润滑切削的最高切削温度比干切削降低了9.42-36.70%。通过冷却液润滑辅助的KDP晶体飞切实验对模型进行验证，实验结果与预测温度吻合较好，最高温度的平均误差约为7.78%。模拟和实验结果均表明，提高进给速度和切削深度或降低切削速度都会导致最高切削温度明显升高。通过冷却液润滑辅助的KDP晶体飞切实验对模型进行验证，实验结果与预测温度吻合较好，最高温度的平均误差约为7.78%。模拟和实验结果均表明，提高进给速度和切削深度或降低切削速度都会导致最高切削温度明显升高。通过冷却液润滑辅助的KDP晶体飞切实验对模型进行验证，实验结果与预测温度吻合较好，最高温度的平均误差约为7.78%。模拟和实验结果均表明，提高进给速度和切削深度或降低切削速度都会导致最高切削温度明显升高。