On the half unit cell intergrowth of Bi2Sr2Ca3Cu4O12 with other superconducting phases in two-step annealed LFZ fibres

resumo

Two-step annealed laser floating zone fibres of BiSr2Ca3.3Cu5.3O23 nominal composition are investigated by high resolution transmission electron microscope and X-ray energy dispersive spectrometry. HRTEM images evidence the presence of the 2234 structure as half unit cell intergrowths with 2223 and 2212 phases. Based on the absence of liquid phase at superconducting grain boundaries and on the interface types between intergrowth domains, two kinds of solid state mechanisms are proposed to explain the development of 2234 intergrowths: (i) the local exchange of CaCuO2 bilayers between contiguous 2223 half unit cells; (ii) the pipe-diffusion of Ca, Cu and O ions from Ca cuprates through edge dislocations towards 2223 half unit cells. (C) 2003 Elsevier B.V. All rights reserved.

palavras-chave

HEAT-TREATMENT; KINETICS; TRANSFORMATION; GROWTH; TAPES; MICROSTRUCTURE; TEMPERATURE; NUCLEATION; POWDER

categoria

Physics

autores

Yang, L; Costa, FM; Lopes, AB; Silva, RF; Vieira, JM

nossos autores

Partilhe este projeto

Publicações similares

Usamos cookies para atividades de marketing e para lhe oferecer uma melhor experiência de navegação. Ao clicar em “Aceitar Cookies” você concorda com nossa política de cookies. Leia sobre como usamos cookies clicando em "Política de Privacidade e Cookies".