PSI - Issue 23

Keng Jiang et al. / Procedia Structural Integrity 23 (2019) 451–456

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Keng Jiang et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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5. Conclusion

In this paper, a numerical approach to study the microscopic progressive fatigue damage evolution of WC-Co hardmetals is presented. The developed modeling technique allows a precise reconstruction of the microstructure. Suitable material models are adopted to simulate the fatigue process at a microlevel. FE simulation result implies that, under a fatigue regime, microcracks are usually initiated in the ductile phase due to the accumulation of plastic strain after several cycles. Consequently, the coalescence of these microdefects results in the formation of subcritical cracks. This process is consistent with experimental observations, in which the susceptibility of the ductile binder to the fatigue property are usually discovered (Llanes et al. (2002)). The effect of micro- and mesoscopic residual stresses due to the cooling history in production process on the fatigue property is also studied. 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