Effect of Y-junction nanotubes on strengthening of nanocomposites

A dislocation model is proposed which describes the strengthening effect of Y-junction nanotubes in nanocomposites. In the model, nanotubes slip along the nanotube/matrix interface through the motion of prismatic dislocation loops. When such a loop meets a Y-junction of nanotubes, it needs a critical shear stress to bypass the junction. It is shown that the critical stress increases with decreasing nanotube radius and wall thickness. Thus, the thinnest nanotubes should provide the most effective strengthening and toughening of such nanocomposites.