An experimental investigation on Inconel 718 interrupted cutting with ceramic solid end mills

• Published in: International journal of advanced manufacturing technology 2021-12, Vol.117 (7-8), p.2173-2184
• Main Authors: Parenti, Paolo, Puglielli, Francesco, Goletti, Massimo, Annoni, Massimiliano, Monno, Michele
• Format: Article
• Language: English
• Subjects: Aerospace industry; CAE) and Design; Carbide tools; Ceramic tools; Ceramics; Chipping; Computer-Aided Engineering (CAD; Cutting force; Cutting parameters; Cutting speed; Cutting wear; End milling cutters; Engineering; Heat resistant alloys; Industrial and Production Engineering; Integrity; Machine shops; Mechanical Engineering; Media Management; Milling (machining); Mills; Nickel base alloys; Original Article; Signal monitoring; Signal processing; Superalloys; Surface stability; Tool life; Tool wear; Turbine blades; Wear mechanisms; Workpieces
• ISSN: 0268-3768; 1433-3015
• DOI: 10.1007/s00170-021-07148-6

Solid ceramic end mills for machining heat resistant super alloys (HRSA) have the potential to generate higher material removal rates, up to one order of magnitude, with respect to standard carbide tools. The machining operations in aerospace industry, where large removals are required to obtain tiny and slender parts like turbine blades, is a cost-intensive task that can benefit of the adoption of ceramic solid end mills. However, these tools show a quite limited tool life, especially when used with interrupted tool engagement strategies. Moreover, they might induce heat-related problems in the workpiece material surface integrity. This paper investigates the cutting and the tool wear during milling Inconel 718 with solid ø12 mm cutting end tool made by SiAlON. The wear mechanisms are studied together with their effects on process signals as cutting forces and power, measured via external and CNC integrated sensors. The carried experimental campaign allowed to find out that tool clogging and edge chipping were the primary cutting phenomena leading the tool wear. Cutting strategy (downmilling or upmilling) produced different results in terms of tool wear sensitivity and process outputs whereas upmilling configuration showed the best results in terms of cutting signals stability and surface integrity. At the same time, cutting speed was found to increase the cutting power more in upmilling than downmilling cutting. The analysis of the forces and power demonstrated that the typical tool wear mechanisms can be traced by signal monitoring due to their high impact on cutting processes. This fact shows the good potential of signal monitoring for a better tool life evaluation.