The dependences of the path of leading dislocations in indentation rosette rays upon the load, loading time and indentation temperature (260 to 373K) were studied for C60 fullerite crystals. The dislocation mobility parameters were estimated. The exponent, m, characterizing the stress dependence of the dislocation velocity depended upon the structural perfection of the crystal and ranged from 2.3 to 24.5, the activation energy for dislocation motion was equal to 0.4 to 0.5eV, and the velocities of the leading dislocations in indentation rosette rays were between 10−5 and 10−4cm/s. The data from micro-and macromechanical experiments were shown to agree with each other. The dislocation mobility was assumed to be controlled by dislocation interactions with local barriers.

Dislocation Mobility in C60 Fullerite Crystals. L.S.Fomenko, S.V.Lubenets, Y.A.Osipyan, V.I.Orlov, A.N.Izotov, N.S.Sidorov: Physics of the Solid State, 2007, 49[4], 800-4