Comparative tool wear study based on drilling experiments on CFRp/Ti stack and its individual layers
Comparative tool wear study based on drilling experiments on CFRp/Ti stack and its individual layers
复制标题
DOI：
10.1016/j.wear.2014.05.007
复制
发表时间：
2014-09
期刊：
影响因子：
5
通讯作者：
Xin Wang;P. Kwon;C. Sturtevant;Dave Kim;Jeff Lantrip
中科院分区：
文献类型：
--
作者：
Xin Wang;P. Kwon;C. Sturtevant;Dave Kim;Jeff Lantrip
碳纤维增强塑料/钛(CFRP/Ti)复合材料电堆因其高比强度在航空航天工业中得到了广泛的应用。钻削是航空航天工业中应用最广泛的加工工艺之一。然而，目前碳纤维/钛复合材料电堆钻削过程中的磨损机理尚不完全清楚，阻碍了碳纤维/钛电堆钻头的发展。本文介绍了碳化钨钻头在碳纤维/钛复合板及其单板(碳纤维复合板和钛复合板)上的对比钻削试验。本研究使用的超硬陶瓷涂层包括Al_xTi_1、−_xN和纳米复合材料(由Si3N_4基质包裹的纳米AlTiN颗粒)。仅钻削碳纤维时，刀具磨损以刃圆磨损为主。当钻削纯钛时，严重的刃口切屑和后刀面磨损大大降低了刀具寿命。令人惊讶的是，对于我们实验中使用的每个钻头，钻取CFRP/Ti堆的刀具寿命比仅钻钛的刀具寿命提高了三倍以上。这一显着改善的主要原因是消除了仅钻钛时普遍存在的严重切边现象。在钻削CFRP/Ti叠层时，CFRP层中的碳纤维去除了钛的粘结，并使切边光滑，从而消除了严重的切边现象。不考虑纯钛钻削时的严重刃口剥落，CFRP/Ti叠层钻削后的总磨损量接近纯钛钻削后刀面磨损和碳纤维复合材料钻削刃圆磨损的磨损量之和。由于碳纤维/钛复合片钻头在钻削过程中消除了严重的切边现象，涂层钻头具有良好的抗切边性能和抗后刀面磨损性能，与未涂层钻头相比没有明显的优势。
Carbon fiber reinforced plastic and titanium (CFRP/Ti) stacks are being widely used in aerospace industries due to its high strength-to-weight ratio. Drilling is one of the most widely used machining processes in aerospace industries. However, the wear mechanism in the drilling process of CFRP/Ti stack is still not fully understood deterring the development of new drills for the stacks at the present time. This paper presents the comparative tool wear study based on the drilling experiments on CFRP/Ti stack as well as its individual plates (CFRP-only and Ti-only) with uncoated and coated tungsten carbide drills. The ultra-hard ceramic coatings used for this study include AlxTi1−xN and nanocomposite (nanocrystalline AlTiN grains surrounded by Si3N4matrix). The dominating tool wear mode when drilling CFRP-only was edge rounding wear. When drilling Ti-only, the severe edge chipping and flank wear substantially reduce the tool life. Surprisingly, the tool life in drilling CFRP/Ti stack was improved more than three times of that in drilling Ti-only for each drill used in our experiment. The main reason for the remarkable improvement comes from the elimination of severe edge chipping prevalent in drilling Ti-only. In drilling CFRP/Ti stack, the severe edge chipping was eliminated by the carbon fibers in CFRP layer brushing off the Ti adhesion and smoothing the cutting edge. Discounting the severe edge chipping in drilling of Ti-only, the total wear volume after drilling CFRP/Ti stack is close to the sum of the wear volumes from the flank wear in drilling Ti-only and the edge rounding wear in drilling CFRP-only. Because the severe edge chipping was eliminated in drilling CFRP/Ti stack, the coated drills with the excellent resistance against edge chipping and the better resistance against flank wear did not show substantial advantages over the uncoated drill.