Isothermal annealing studies on vacancy and interstitial loops in single crystal graphite

摘要: Abstract Single crystals of graphite were treated in various ways to obtain either vacancy or interstitial loops ∼ 103 A diameter. The character the was determined by diffraction contrast electron microscope. Thin foils from these isothermally annealed at temperatures between 2100° and 2600°c. diameters a pre-selected area measured after successive periods annealing. It found that this temperature range, both out dislocation climb. In some circumstances, large grew whilst smaller ones shrank. Using an anisotropic diffusion model it has been shown types loop with common activation energy 8·3 + 0·3 ev. This identified as E f ½(E ma+E mc), where is formation diffusing defect, ma mc migration energies parallel perpendicular basal planes respectively. analysis shows type experiment cannot yield infor...