| Cutting temperature during high speed machining operation has been recognized as a major factor that influences the tool life, the machined surface integrity and its quality. It has been an important research project.In the paper, the heat transfer model of cutting temperature field has been built. Theoretic study about shear plane heat source and tool-chip interface friction heat source is carried out with the method of heat source. The temperature field distribution of chip and workpiece due to shear plane heat source is determined by this method. The temperature field distribution of chip and tool due to tool-chip interface friction heat source is also obtained. Then temperature field distribution of chip and tool due to combined both sources is derived. This paper builds thermo-viscoplastic model and carries out the finite element simulations of cutting temperature field by finite element software. The temperature field distribution indicates that the highest temperature focuses on the local region near to the tooltip at the tool-chip interface. From the dynamic cutting simulation, the curve of the highest temperature variation with step indicates that at the early stage of cutting, temperature increases very rapidly arid its change is slower and slower during cutting period until reaching steady state. When reaching steady state cutting, the temperature variation curve of machined surface along cutting depth direction indicates that the temperature only a thin layer of work piece rise while the local workpiece temperature doesn' t change much. During steady state cutting process, the maximum temperature occurs away from the tooltip rather not the tooltip can be obtained from the rake face temperature curve of the tool-chip interface. The effect of the cutting parameters such as cutting velocity, the cutting depth, rake angle on the cutting temperature has been studied. The computed conclusions show good agreement with those of literatures.
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