An experimental investigation on the machining characteristics of Nimonic 75 using uncoated and TiAlN coated tungsten carbide micro-end mills

详细信息    查看全文

• 作者：Niharika Swain^a ; Vijay Venkatesh^a ; ¹ ; Praveen Kumar^a ; G. Srinivas^a ; S. Ravishankar^b ; Harish C. Barshilia^a ; ^{harish@nal.res.in}
• 关键词：Micro-milling ; Nickel superalloys ; Tool wear ; Slot geometry ; Burr formation
• 刊名：CIRP Journal of Manufacturing Science and Technology
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：16
• 期：Complete
• 页码：34-42
• 全文大小：2710 K
• 卷排序：16

文摘

We report the machining characteristics and machinability of a nickel based superalloy in this study. A micro-milling operation is loaded on Nimonic 75 using uncoated and TiAlN coated tungsten carbide micro-end mills. A full factorial design of experiments was devised to optimize the machining conditions to reduce the flank wear on the tool surface. The optimized machining conditions for uncoated micro-tools were found to be a cutting speed (vc) of 13 m/min and a feed rate (fz) of 6 mm/min. Following this, the tools were coated with TiAlN using a semi-industrial four-cathode reactive pulsed direct current unbalanced magnetron sputtering system. Further experiments were then performed using these optimized machining conditions using both uncoated and TiAlN coated micro-tools in order to ascertain the tool wear and surface integrity. The change in geometry of the machined slot was estimated based on the variation in tool radius of the micro-end mill with progression of the operation. A direct comparison was made between the results observed using both uncoated and TiAlN coated tungsten carbide to illustrate the effect of the nanocomposite TiAlN coating. It was seen that TiAlN coated micro-tools exhibited a superior performance as compared to the uncoated ones with respect to tool life and micro-burr formation.