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The relationship between the cutting speed, tool wear, and chip formation during Ti-5553 dry cutting. International Journal of Advanced Manufacturing Technology, Springer Verlag, 2015Verlag, , vol.76 (n°5-8), pp. 893-912. 10.1007 Any correspondence concerning this service should be sent to the repository administrator: staff-oatao@inp-toulouse.fr OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. DOI 10.1007/s00170-014-6326-1 The relationship between the cutting speed, tool wear, and chip formation during Ti-5553 dry cutting Vincent Wagner · Maher Baili · Gilles Dessein Abstract Over the past several years, titanium alloys have been increasingly used in aeronautics. However, they are considered to have poor machinability. The Ti-5553 nearbeta titanium alloy is used in aeronautics to replace Ti-64 and for the production of structural parts, such as landing gears. Due to the low thermal properties and the high mechanical properties presented in this work, this alloy is considered difficult to machine. This work is devoted to understanding the relationship between the chip formation, the cutting process, and the tool wear. The first section studies the evolution of the tool wear. The tests show that tool wear occurs in three steps mainly due to the cutting process and the chip formation. To clarify these points, a section is dedicated to the chip formation and cutting processes. An analytical model is also used to quantify stresses, temperatures, and friction inside the workpiece material and at the tool/chip interface. Chip formation is commonly studied using a tool without wear, which can affect the cutting tool geometry. To verify chip formation and the cutting process during machining, a section describes the chip formation and the cutting processes using worn tools.

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. Abstract. The manufacturing of aeronautic parts with high mechanical properties requires the use of high performance materials. That's why; new materials are used for landing gears such as the titanium alloy Ti-5553. The machining of this material leads to high cutting forces and temperatures, and poor machinability which requires the use of low cutting conditions. In order to increase the productivity rate, one solution could be to raise the workpiece initial temperature. Assisted hot machining consists in heating the workpiece material before the material removal takes place, in order to weaken the material mechanical properties, and thus reducing at least the cutting forces. First, a bibliography review has been done in order to determine all heating instruments used and the thermal alleviation that exists on conventional materials. An induction assisted hot machining was chosen and a system capable to maintain a constant temperature into the workpiece during machining (turning) was designed. Trails permit to identify the variation of cutting forces according to the initial temperature of the workpiece, with fixed cutting conditions according to the TMP (Tool-Material-Pair) methodology at ambient temperature. Tool life and deterioration mode are identified notably. The results analysis shows a low reduction of specific cutting forces for a temperature area compatible with industrial process. The reduction is more important at elevated temperature. However, it has consequences on quality of the workpiece surface and tool wear.