Finite element analysis of the effect of tool rake angle on brittle-to-ductile transition in diamond cutting of silicon

Brittle-to-ductile transition plays a crucial role in ultra-precision machining of hard-brittle materials. In the present work, we investigate the brittle-to-ductile transition in diamond grooving of monocrystalline silicon by finite element modeling and simulation based on Drucker-Prager constitutive model. The brittle-to-ductile transition behavior is distinguished by analyzing evolutions of chip profile and cutting force. Corresponding diamond grooving experiment using the same machining configuration with the finite element simulation is also carried out to derive the critical depth of cut for the brittle-to-ductile transition. The comparison of experimental value of the critical depth of cut and predicted one by the finite element simulation demonstrates the high accuracy of as-established finite element model. Subsequent finite element simulations are performed to investigate the influence of rake angle of cutting tool on both diamond grooving and conventional diamond cutting with a constant depth of cut, which demonstrates a prominent dependence of brittle-to-ductile transition of silicon on the rake angle ranging from − 60° to 0°. And a critical rake angle for the most pronounced ductile machinability of silicon is found.