Influence of External Fields on Sintering

  • Yuri Kornyushin

Abstract

Two types of driving forces caused by the presence of external fields are described: one type arises due to the evolution of the heat in the volume of a sample (electric contact, hf, inductive heating or penetrating radiation, e.g., neutrons could be the sources of the heat); another type of the driving forces arises due to the energy of the field (electric, magnetic), present in the bulk of a polar material. Influence of these driving forces on sintering, structure and properties is discussed. The role of mobile and immobile dislocations, grain boundaries, and pores is considered. Cycling and pulsing regimes of sintering are investigated.

Porous polar materials are studied on the basis of the Clausius-Mossotti approximation. Equilibrium shape of a pore in a polar material is calculated. It’s contribution to the anisotropy of a sample is discussed. Peculiarities of the kinetics of pores in polar materials in external field are regarded.

Keywords

Porosity Migration Furnace Anisotropy Enthalpy 

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Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Yuri Kornyushin
    • 1
  1. 1.Racah Institute of PhysicsThe Hebrew UniversityJerusalemIsrael

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