Alonso Pinillos Unai, Fernández Vidal Severo Raúl, Calamaz Madalina, Girot Mata Franck Andrés
Department of Mechanical Engineering, University of the Basque Country (UPV/EHU), 48013 Bilbao, Spain.
Department of Mechanical Engineering & Industrial Design, Faculty of Engineering, University of Cadiz, Av. Universidad de Cadiz 10, E-11519 Puerto Real-Cadiz, Spain.
Materials (Basel). 2019 Sep 4;12(18):2843. doi: 10.3390/ma12182843.
The present contribution on tool wear during the drilling of carbon fiber composite materials (CFRP)/Ti stacks intends to determine (i) if the adhesion of titanium to carbide is mechanical or chemical, (ii) the possible diffusion path, (iii) if the titanium is the only element involved in the adhesion and (iv) the role of the CFRP in this wear. The overall tool wear is not the sum of the wear in each material and there is a multiplicative effect between them. It has been pointed out that the maximum temperature reached during drilling is higher than 180 °C, 400 °C and 750 °C respectively in the CFRP and Ti plates alone and in the Ti part of the stack. As tungsten carbide CW is not in equilibrium with titanium above 250 °C, the diffusion path is CW/(Ti,W)C/Ti as confirmed by Auger analysis. For temperatures above 500 °C, (Ti,W)C becomes very sensitive to oxidation allowing a friable oxycarbide (Ti,C,O) to form, which explains the erosion of the tool. The CW is therefore the weakest link in the drilling of CFRP/Ti stacks. Improving the performance of the tool involves the use of a coating, the development of a tool material having low chemical affinity with Ti and/or the use of cryogenic lubricant.
本文关于碳纤维复合材料（CFRP）/钛合金叠层钻孔过程中的刀具磨损，旨在确定：（i）钛与碳化物的粘附是机械性的还是化学性的；（ii）可能的扩散路径；（iii）钛是否是参与粘附的唯一元素；以及（iv）CFRP在这种磨损中的作用。整体刀具磨损并非每种材料磨损的总和，它们之间存在相乘效应。有人指出，钻孔过程中达到的最高温度在单独的CFRP、钛板以及叠层的钛部分中分别高于180°C、400°C和750°C。由于碳化钨（CW）在250°C以上与钛不平衡，俄歇分析证实扩散路径为CW/(Ti,W)C/Ti。对于500°C以上的温度，(Ti,W)C对氧化变得非常敏感，从而形成易碎的氧碳化物（Ti,C,O），这解释了刀具的磨损。因此，CW是CFRP/钛合金叠层钻孔中最薄弱的环节。提高刀具性能涉及使用涂层、开发与钛化学亲和力低的刀具材料和/或使用低温润滑剂。
