Thermal modeling and experimental verification of actively driven rotary turning process

Official URL: http://risc01.sabanciuniv.edu/record=b1649216 (Table of Contents)

With the increasing demand in several industries, including aviation, aerospace, defense, automotive, energy, different materials for better performance, higher strength to weight ratio such as superalloys are started to be used. These newly used materials are needed due to their superior mechanical and chemical properties, which can be maintained at extreme conditions that also makes them strenuous for the machining procedures, thus being labeled difficult to machine alloys. Machining these materials with the conventional methods result in high cutting temperatures and stresses that lead to a problematic operation. The effects of these problems are seen in the form of higher cutting forces and higher cutting temperatures that mostly reflect on the tool life and the quality of the finished product. To overcome these problems in turning operation a different approach is taken by changing the tool instead of compromising the machining quality and productivity. Rotary cutting tools are introduced as a solution, as the tool has a continuous cutting edge that rotates around its axis and by this way ensuring that the tool is kept cooler. With the rotary movement, the tool distributes and reduces the heat, at every instant of the cutting process a cooler part of the tool comes in contact with the workpiece thus decreasing the temperature during the machining process. This leads to longer tool life and higher surface quality on the finished product. The main aim of this thesis is to understand and expand the knowledge on actively driven rotary turning (ADRT) tools and its mechanics. For this, a heat generation and distribution model is developed, to be able to define machining parameters for these tools in advance. The model is verified with experimental measurements with a thermal camera. Tool temperature for various different cutting conditions and workpieces were investigated. Results of the model are compared with experiments; effects of these conditions are examined and analyzed.