Based on the finite element analysis software ABAQUS, a two-dimensional cutting simulation model for Ti6Al4V is established. In order to investigate the effects of the damage evolution process on the simulation results, the cutting force, cutting temperature, and chip morphology under different damage evolution characteristic parameters (fracture energy) are obtained when the other model parameters (constitutive parameters, initial damage parameters, etc.) are fixed. The research finds that the simulated cutting force and the cutting temperature decrease with the decrease of value of the fracture energy. making the serrated degree of the chip severer. The orthogonal experiments of machining Ti6Al4V are carried out to measure the cutting force at the cutting speed of 180 m/min and feed rate of 0.1 mm/r. By comparing the simulated main cutting force and the serrated degree of the chip with the experimental results, the reasonable value of fracture energy suitable for the established simulation model is determined. The results show that the cutting force and the chip geometry obtained by simulations are in good agreement with the experimental values when the reasonable fracture energy value is used. After eliminating the effects of energy density on the simulation model, four sets of validation experiment are conducted. The simulated results are consistent with the experimental results of the verification experiments, and the accuracy of the fracture energy values is verified.
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