Workpiece subsurface temperature study during aluminum skin milling in slotting and ramping

Abstract

Aluminum alloys are widely used in the industry such as aerospace. This study was motivated by the replacement of the chemical milling of thin aluminum parts with mechanical milling. To remain within requirements of design specifications, this process needs to be tuned and optimized using e.g. cutting forces, vibrations and surface integrity assessments. In aerospace industry, the temperature control is indeed a major issue since the heat generated and transferred to the workpiece during machining can affect the surface integrity and thus the component properties. A heat analysis is ultimately needed to optimize, control and certify a milling process.In this research, embedded thermocouples at specific locations in a 2024-T3 aluminum thin plate subsurface have been used to evaluate local temperatures during machining. Two milling operations have been selected: slotting and ramping. The measurement data showed workpiece temperature increase with the feed reduction. An increase of the internal-temperature is indicated while the cutting tool moves into workpiece from the beginning of the cutting stage to the middle line of the tool-path. Finally, the test results shown that the effect of the feed (both radial and axial) has one of the most significant influence on subsurface accumulated heat, more than the cutting speed.