【作者】 牟娟；

【导师】 徐九华；

【作者基本信息】 南京航空航天大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 碳/环氧复合材料是碳纤维增强树脂基复合材料（Carbon Fiber Reinforced Plastics，CFRP）中重要的一类，具有高的比强度、比模量、比刚度等优点，被广泛应用于航空航天、汽车、能源等领域。在树脂聚合物中，具有良好力学性能的环氧树脂应用最为广泛，因此CFRP常被用来代指碳/环氧复合材料。在CFRP结构件上安装紧固件过程中需要频繁的进行钻孔加工，本文根据CFRP具有的强度大、硬度高、各向异性等特点，对孔加工质量难以保证，钻头寿命短等问题开展了试验研究，主要工作包括：（1）采用硬质合金麻花钻进行CFRP钻削试验，对麻花钻的钻削加工过程进行分析，研究切屑及已加工表面的形成机制。分析麻花钻加工过程中工艺参数对加工缺陷的影响，特别是对分层缺陷与撕裂缺陷的影响。在了解CFRP加工性能的基础上，对麻花钻加工中存在的问题及解决措施进行分析。（2）参考CFRP钻孔工具的发展趋势，使用钎焊金刚石套料钻钻削CFRP。通过对比试验，确定钎焊金刚石套料钻基体的壁厚，磨粒粒度与磨粒排布方式。使用钎焊金刚石套料钻在实际加工常用的工艺参数下进行钻削加工试验，钎焊金刚石套料钻的钻削尺寸精度及孔壁粗糙度均满足精度要求。（3）在同样工艺参数下，可以使用不同磨粒排布的套料钻的来改变单颗磨粒切厚。使用不同磨粒排布的套料钻钻削复合材料层合板，测量加工过程中的钻削力与钻削温度。由于红外温度测量试验仅能测量钻孔出口处温度，又开展钻削温度场仿真对钻削过程中的温度变化进行分析。比较不同套料钻钻削时磨屑与已加工表面形成过程的差异，分析单颗磨粒切厚变化对磨粒加工机理的影响。（4）研究不同磨粒排布的套料钻钻削CFRP时工艺参数对加工缺陷的影响，分析分层缺陷、撕裂缺陷的产生原因。使用钎焊金刚石套料钻在实际加工常用的工艺参数下进行磨损试验，确定套料钻的钻头寿命较硬质合金麻花钻大大延长。从钎焊金刚石套料钻的加工机理入手，分析套料钻加工CFRP时的缺陷产生的模型，推荐钎焊金刚石套料钻实现无缺陷钻孔的工艺规范。更多还原

【Abstract】 With the advantages like superior strength-to-weight, specific modulus, stiffness-to-weight ratios,carbon/epoxy is widely applied in aeronautics and aerospace domain, automobile and energy area, etc.Epoxy is used extensively for the super mechanical properties, so carbon fiber reinforced plastics(CFRP) usually represent carbon/epoxy. Drilling process is required frequently in fastening partinstallation in CFRP parts, while the drilling quality is hard to guarantee and the drill life is quite shortfor the high stiffness and hardness, anisotropy of CFRP. The main works have been done as follows:(1) Based on the CFRP drilling experiments with twist drill, the drilling process has beenanalyzed, and the formation mechanism analysis on chips and machined surface has been studied. Theinfluences of drilling parameters on quality, such as delamination and cracking, have been studied. Asthe machinability of CFRP has been understood, the existed problems during the drilling process withtwist drill and corresponding solutions have been illustrated.(2)Referring to the development trends of tools in CFRP drilling, the brazed diamond core drillwas applied. After experimental comparison, the thickness of brazed matrix, the grit size and gritsdistribution of brazed diamond core drill were decided. By drilling CFRP with brazed diamond coredrill under the common parameters, the drilling accuracy was proved to satisfy the requirements.(3)The undeformed chip thickness changes when using core drills with different grits distributionunder the same drilling parameters. When drilling the CFRP laminate using core drills with differentgrits distribution, the grinding force and temperature were measured. Since only the exit temperatureof holes can be measured with the infrared temperature sensor, the simulation of temperature field hasbeen carried out to analyze the temperature change in drilling. Comparing the formation mechanismof chips and machined surface, the effects of undeformed chip thickness on chips and machinedsurface formation has been studied.(4)Based on the influence of drilling parameters on quality, the causes of damages in drillingwith brazed diamond core drills have been studied. The wear test of brazed diamond core drills wascarried out under the usual parameters to make sure that the life of core drills was much longer thancemented carbide twist drills. From the drilling mechanism of brazed diamond core drills, thecontrolling measures of damages, especially the recommendation of drilling parameters have been putforward.更多还原