Modelling and experimental investigation of temperature field during fly-cutting of KDP crystals
Modelling and experimental investigation of temperature field during fly-cutting of KDP crystals
复制标题
DOI：
10.1016/j.ijmecsci.2021.106751
复制
发表时间：
2021-08-25
影响因子：
7.3
通讯作者：
Zhang Feihu
中科院分区：
文献类型：
--
作者：
Li Chen;Piao Yinchuan;Zhang Feihu
KDP晶体是制作惯性约束聚变和激光倍频核心元件的主要非线性晶体。然而，KDP晶体是一种软脆性材料，易潮解，脆性大，对高温敏感，加工难度大。基于切割生热理论和传热学理论，建立了冷却液润滑下KDP晶体飞切过程中的温度场理论模型。该模型考虑了空气与作功材料之间的热交换、流体与作功材料之间的热交换以及KDP晶体的各向异性。模型预测结果表明，油冷却剂能有效地提高飞切过程中的热扩散率，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割温度。与干切削相比，冷却润滑最高切削温度降低了9.42~36.70%。对KDP晶体在冷却液润滑下的飞切实验进行了验证，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%。模拟结果和实验结果均表明，增大进给速度、降低加工深度或降低加工速度均可明显提高最高加工温度。
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.