The mechanisms and sintering kinetics of wetted Y-Ba-Cu-O powders

摘要

The influence of preliminary wetting of Yba_2CU_3O_7-x powder on the kinetics of their sintering and recrystallization and the evolution of element and phase compositions in the bulk and on grain boundaries was studied by the methods of scanning electron microscopy, X-ray microprobe and phase analysis. It was established that preliminary wetting of powder leads to change in sintering mechanism from diffusion in the bulk (for unwetting powder) to diffusion across the solid state layers that were formed in subboundary and subsurface regions of wetting powders from the products of interaction of phase Yba_2Cu_3O_7-x with wet atmosphere.