Eshelby's energy-momentum tensor is used to provide an analytical expression for the driving force for rafting in the elastic regime in a superalloy with a high volume fraction of γ'. The structure is modelled as a simple cubic array of γ' cubes separated by thin sheets of γ'. During rafting, the γ' particles are constrained to remain tetragonal prisms. For tension along a cube axis. the driving force is proportional to the product of the tension σ, the fractional difference ? of lattice parameters of γ' and γ and the fractional difference m of their elastic constants c_11-c_12.
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