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FEM simulation of Interface cracks in twolayered coatings by Abaqus/CAE

Sir/Madam,

 I have Ni based metas over which i coated two layers first one is metallic powder(NiCoCrAl like) coating and second one (top layer) of ceramic materials is coated over first one.

The model is constrained in the radial direction on the axis (at r = 0) in order to simulate a full cylinder with no inner ole. In order to correctly represent a slice taken out of a long cyl-inder, nodes at the bottom of the model are constrained in axial irection, those on the top of the model are allowed to move in the axial direction, but their movement is constrained such that ll these nodes must have the same displacement.At high temperature, the oxide layer is growing due to oxidation of the bond coat. This process causes a volume increase of the material which in turn causes rowth stresses. The growth is modeled as an anisotropic swelling f the oxide layer with a parabolic growth constant of 1.5 x10-17m2/s and an anisotropy ratio of 10 (i.e., growth in thickness irection is 10 times larger than growth in lateral direction.The geometry was meshed using approximately 15,000 four-node elements with selectively reduced integration. Strong mesh efinement was used in the region where cracks occur.The model is thermally loaded, starting in a stress-free state at a emperature of 20 C. Within 60 s, it is heated to 1000 C, held at his temperature for 10000 s, and cooled back in another 60 s to 0 C. Since it is known that cracks in thermal barrier coating growth low temperatures, the crack propagation algorithm is only acti-vated at 20 C.under below condition Abaqus asks for the values of  Eq.stress order,time order  and power law multiplier under plasticity of creep in material property.plz how can we get thse values?

My model geometery is below:

 

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