Preliminary investigation on ultra-precision diamond turning of titanium alloys using thermoelectric cooler fixture

The low thermal conductivity of titanium alloys causes an accumulation of high cutting heat at the tool/workpiece interface and thus deteriorates surface integrity of the machined surface in ultra-precision machining (UPM). In response of this underlying source causing the poor machinability of the materials in UPM, in this study, a novel fixture composed of thermoelectric cooler (TEC) is firstly developed and applied into single point diamond turning (SPDT) of titanium alloys, aiming to dissipate the cutting heat in the machining process. The TEC contacted with workpiece during the whole turning process and caused a dissipation of cutting heat from the workpiece. By using the fixture with TEC device, the cutting force variation and surface roughness involved in SPDT were reduced. This study presents the preliminary results of application of TEC fixture on UPM of titanium alloys and shows the feasibility of the use of TEC device in UPM area, suggesting a new approach to resolve the problematic high cutting heat of titanium alloys in UPM.