| High speed cutting progress, which has the characteristics of high productivity and high machining precision, has become a new focus since its concept was put forward. Compared with the traditional machining method, numerical methods are favored by many researchers, not only because they can overcome the disadvantages of conventional testing method to achieve the quantitative analysis of high speed cutting process, but also because they have the advantages of small investment and short period.In this paper, numerical methods, such as finite element method, material point method and boundary element method, were studied respectively. According to their pros and cons, we presented the coupling technology of these numerical methods and developed the corresponding programs. Based on the existing theory of metal cutting and mechanics, we simulated and analyzed the metal cutting process under the high speed condition by considering various nonlinear factors, which can provide references for further theoretical research and engineering application.Firstly, following the existing work, the effective elastic properties of doubly periodic inclusions are considered by using an iterative FE-BE coupling method. As we have known, the FEM is well suited for inhomogeneous and anisotropic materials, while the BEM has been considered to be an efficient approach for solving various elastic problems. Therefore, based on a rectangular cell model, the considered problem is decomposed into two subdomains: one is the inclusion part that is calculated by the finite element method and the other one is the medium part that is solved by the boundary element method. Then, balance equations of these two subdomains are established respectively. Along the common interface, displacement compatibility and force equilibrium must be satisfied. The final solution can be obtained by iterative technique. Numerical examples studied composites containing irregular anisotropic inclusions and regular functional graded inclusions, respectively. By comparing the results with other numerical solutions, it shows the correctness and the validity of the present method.Secondly, an iterative FE-BE coupling algorithm is proposed for 2D time domain responses. Based on the platform of ABAQUS, this algorithm is implemented through user subroutine UEL, which makes the boundary element method and commercial software ABAQUS combine together successfully. In this way, the user can not only benefit from many built-in features of the ABAQUS, including pre- and post-processing options, but also deal with systems with infinite extension and regions of high stress concentration by using the BEM as a supplement. Through the secondary development techniques, on one hand the user can benefit from the common software platform, on the other hand can establish professional models based on their specific questions. Besides, it is much easier to maintain one or several subroutines than the whole program. Numerical examples considered the elastic-plastic dynamic problem and infinite domain problem. All numerical results show the availability that the coupling algorithm can be embedded into ABAQUS software.Finally, the coupling algorithm of the BEM and the MPM is proposed to simulate high speed cutting problems. In the cutting progress, severe elastic-plastic deformation is taken place in regions containing chip formation process, whereas for the region far under the machined sub-surface of the workpiece, only elastic deformation occurs. Therefore, based on these characteristics of the model, the coupling algorithm of the BEM and the MPM is presented, where the MPM is used to study the severe deformation while the BEM is for the elastic area. Numerical examples simulated the cutting progress of Ti6A14 V at different working speed by the presented coupling method. The numerical solutions are compared with the experimental results. Besides, the chip morphology, cutting force and cutting temperature are analyzed respectively at different speed. |
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