Prediction of cutting forces including tool wear in high-feed turning of Nimonic® C-263 superalloy: A geometric distortion-based model

Abstract

The hottest parts of aerospace components are often made of heat-resistant materials. Due to the high requirements in such parts and accelerated wear rates, machining is a challenging task. Recently, new high-feed machining strategies were launched by tool developers. The main idea is ​​using extremely low side cutting edge angles Kr so that high feeds and low chip thicknesses are both possible. These tools are supposed to be decisive for greater productivity rates. However, tool wear’s traceability is the key in order to replace them before dramatic failure. Additionally, the machining of such aggressive materials must be assisted by high pressure cooling. To reduce the environmental footprint, cryogenic techniques look promising. This work proposes a prediction cutting model for high feed turning of Nimonic© C-263 superalloy including tool wear. It allows to consider the geometric tool deterioration, which is the key mechanism in the evolution of cutting forces on this superalloy. The concept of reducing side cutting edge angle and its benefit on productivity is also explored. Besides, oil emulsion and CO2 cryogenic conditions are also compared. The wear prediction model showed good agreement with the experimental results by obtaining relative errors of less than 5 % using cutting speeds lower than 100 m/min and less than 14 % for higher speeds. The benefit of reducing the side cutting edge angle on tool life 8 (from 90° to 30°) was also demonstrated by increasing tool life x3 (from 8 to 24 min). Notches were removed. In contrast, using cryogenic conditions do not seem to be a clear advantage over this type of superalloy. Finally, optimum conditions were found: using vc = 70 m/min, f = 0.2 mm/rev and = 1 mm, good surface finish, chip control and tool life can be satisfied.