Fatigue Coffin-Manson model

Here / is the cycle frequency, Nf the number of cycles to failure, and AT the temperature difference. The Coffin-Manson model is widely accepted for describing material degradation (e.g., solder materials), fatigue fracture, and crack propagation. 

Example 5. An example of modeling coupled failure mechanisms is the failure behavior model for components subjected to the coupling of fatigue and creep (Collins et al. 2009). For components subjected to only low-cycle fatigue, a Coffin-Manson model will approximate the failure behaviors quite well (Equation (14)). In equation (14), Ay is the TTF in cycles, A/ is the plastic strain range and both m and C are constants associated with material properties. 

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