Hardening mechanisms in a γ′-L12 ordered phase containing disordered γ precipitates

Abstract

Strengthening mechanisms in an ordered intermetallic compound containing coherent precipitates of lower antiphase boundary energy than the matrix have been investigated on the basis of the interaction between deformation induced dislocations and disordered precipitates in an L12 ordered Ni3(Al, Ti). Extra work necessary to pull out the dislocations from the precipitate is dependent on the difference in antiphase boundary energy between the matrix and the precipitate, the size and volume fraction of the precipitate. The strength of γ′-Ni3(Al, Ti) L12 ordered phase containing fine precipitates of the disordered γ phase has been examined using the proposed model. The model can explain almost quantitatively the age hardening behavior of the ordered Ni3(Al, Ti) phase.