With the help of combining continuum damage mechanics and viscoplastic theory

the unified viscoplastic constitutive model [1] developed by authors is modified.A unified viscoplastic constitutive damage model of anisotropic materials under the alternative effect of creep and fatigue load is established.The creep and fatigue property as well as their damages for monocrystalline alloys DD3 have been predicted according to this model.The durability and damage under the alternative effect of the creep and fatigue load for the material under cyclic loading.The predicted results are compared with test data.