The generation, equilibrium and emission of dislocations from an elastically mismatched particle/matrix interface were studied under the combined effects of thermal and mechanical loading. Energy considerations were used to treat the generation, equilibrium and instability conditions, and force-balancing was used to predict the equilibrated loop shape. When the mismatch strain exceeded the generation limit, which was particle-size dependent, the generation of dislocations lowered the system energy. A stable dislocation loop segment would then be generated and bulge out from the particle/matrix interface. At the point of instability, which was also particle-size dependent, a dislocation would be emitted from the particle. Analytical expressions were derived which described generation, equilibrium and instability. A dislocation-generation mechanism-map was obtained for the analysis and design of particle-reinforced composites.

Modelling the Generation, Equilibrium and Emission of Dislocations at Elastically Misfitting Particles. X.J.Xin, G.S.Dähn, R.H.Wagoner: Acta Materialia, 1998, 46[17], 6131-44