芳纶纤维增强树脂复合材料液氮冷却钻孔试验

芳纶纤维增强树脂（AFRP）复合材料是一种公认的难加工材料，加工中极易出现毛刺、烧蚀等缺陷，目前缺乏对其有效的加工工艺方法。为提高其加工质量，研究了液氮作为冷却介质的AFRP复合材料钻孔试验。在相同切削参数下进行了干式切削和超低温加工对比试验，测量了切削过程中的轴向切削力和孔临近区域的温度，并计算了孔的进出口毛刺面积和分层因子，分析了AFRP复合材料缺陷的成因，探讨了不同加工条件下缺陷的变化规律。结果表明:与干式切削相比，采用液氮超低温冷却加工的切削力升高了约15.2%，切削温度降低了约141.6℃，毛刺面积减少了约24.7%，因切削热产生的烧蚀现象得到抑制，明显改善了AFRP复合材料的加工质量。 

Experiment of liquid nitrogen cooling drilling test of aramid fiber-reinforced polymer composites

The aramid fiber-reinforced polymer(AFRP)composite are proverbial difficult-to-machining materials,it is easy to generate defects of burr and ablation.At present,there is lacks of the effective processing methods for AFRP composite.In order to raise processing quality,the drilling experiment of AFRP composite using liquid nitrogen as cooling medium was studied.A comparative test of dry cutting and cryogenic machining under the same cutting parameters was carried out.The axial cutting force and temperature in the vicinity of the hole in the cutting process were measured,and the delamination factor and fuzzing area after drilling were calculated.The causes of AFRP composite machining defects were analyzed,and the changing rules of defects under different cutting conditions were discussed.The results show that compared with dry cutting,the cutting force increases by 15.2%,the cutting temperature decreases by 141.6℃,and the burr area decreases by 24.7%.The ablation phenomenon caused by cutting heat is inhibited,visibly improving the processing quality of AFRP composite when liquid nitrogen ultralow temperature cooling is used.