Based on the idea of nonlocal theory

peridynamics describes the movement of material particles by solving spatial integral equations. It is suitable for describing the crack growth and fracture behavior of workpiece materials during severe plastic deformation in cutting process. In this paper

the elastoplastic constitutive model of Ti

2

AlNb is constructed based on ordinary state-based peridynamics

and material failure and contact criteria are developed. By solving discrete basic motion equations

a state-based peridynamics numerical model is established to study the cutting process of Ti

2

AlNb alloy. Then the chip formation process for orthogonal c

utting of Ti

2

AlNb is simulated and analyzed. The results demonstrate that the peridynamics method can accurately simulate the material deformation and damage evolution during machining of Ti

2

AlNb. The error between the predicted chip shear angle of 40.23° and the experimental result of 38.89° is 3.45%. The full width at half maximum of the damage spatial distribution is defined as the width of the primary shear zone

and the predicted value is 0.06 mm with an error of less than 7%.