Deformation Mechanism Map for Creep and Superplastic Deformation in <tex>$YBa_2Cu_3O_{7-x}$</tex>  Ceramic Superconductors

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J. Korean Ceram. Soc. > Volume 33(6); 1996 > Article

Journal of the Korean Ceramic Society 1996;33(6): 718.

$YBa_2Cu_3O_{7-x}$ 세라믹 초전도체의 크리프와 초소성변형에 대한 변형기관도

윤존도, 초우예¹

경남대학교 무기재료공학과
¹리하이 대학교 재료과학공학과

Deformation Mechanism Map for Creep and Superplastic Deformation in $YBa_2Cu_3O_{7-x}$ Ceramic Superconductors

ABSTRACT

Deformation mechanism map of Langdon-Mohammed type for YBa2Cu3O7-x superconducting ceramic was constructed by considering mechanisms of Nabarro-Herring Coble and powder-law creep and grain boundary sliding (GBS) with an accommodation by grain boundary diffusion. The map was found consistent with experi-mental results not only of the creep the also of the superplastic deformation. It showed the transition from interface reaction-controlled to the grain boundary diffusion-controlled GBS mechanism at about 1 ${mu}{textrm}{m}$ grain size and 100 MPa flow stress in agreement with the experimental results.

Key words: Ceramic superconductors, Deformation mechanism map, Plastic and superplastic deformation, Diffusional and powder-law creep, Grain boundary sliding, Grain boundary diffusion controlled, Interface reaction controlled