Finite Element Simulation Of Cutting Hardened Steel With High Speed

Manufactures continually search for new and lower cost methods to manufacture products as well as more efficient application of existing process technologies. High-speed cutting(HSC) is an important part of advanced manufacturing technology, and has been a major method for cutting high hardness materials such as hardened steel. The use of PCNB tool can meet these machining requirement instead of grinding or reducing grinding.Based on the theory of finite element method, considered characteristic of high speed hard cutting hardened steel and used both MSC.Marc and ABAQUS/Explicit software, the finite element model of two-dimension plane strain fit for hard cutting was built to simulate the process of continuous and segmental chip and the tool wear in hard cutting. The nonlinearity of material was simulated by considering the temperature effect on material physical and mechanical property and the change of flow stress that depends on the plastic strain, strain rate and temperature. The forming of chip was simulated by remeshing technology in MSC.Marc and the shear failure criteria, element deletion and adaptive remeshing technology in Abaqus/Explicit 6.5; the finite element methods of updated Lagrangian and Arbitrary Lagrangian Eulerian formulation were adopted for deal with the problem of geometry nonlinearity in hard cutting; coulomb friction model was adopted for simulating the friction problem in hard cutting; tool wear was simulated by combining ABAQUS and Python programming language. Cutting force increased proportionally according to cutting width and the force had cyclical variation following the forming and development of segmental chip; temperature of cutting area increased a little; the residual stress change rules of machined surface are the same when using honed and chamfered tools; Due to the low mechanical strength in three kinds of ordinary edge preparation (sharp-edge, hone and chamfer), the sharp-edged tool is not fit for hard cutting of hardened steel. Distribution of temperatures is better and lower in machined surface with chamfer tools than honed tools, which is useful for machined surface integrity. Tool wear can be simulated by combining ABAQUS and Python programming language.In this thesis, the hardened bearing steel GCr15 (HRC60-62) is selected to be the material, a series of cutting forces experiments were done with AMBORITE DBA80 PCBN tool which was supplied by Element Six with CA6140 lathe.Compared experiment with simulation results, FE simulation of cutting force, cutting temperature and residual stress change rules of the machined surface have good precision(experiment results were little higher than simulated), and can simulate the process of continuous and segmental chip and the tool wear. The simulated methods adopted in this thesis could partially replace experimental research, and extended the applying of finite element theory, and accelerated the research of hard cutting theories.