Diffusion in carbides and nitrides : Unsolved problems
Diffusion measurements in the hard ceramic carbides and nitrides with their very high melting points are difficult to perform. Many of these materials are largely non-stoichiometric and can show ordering of the existing large vacancy concentrations in the non-metal sublattice. Often, only rather impure, porous specimens (often containing second phases) are available, and frequently suitable radioactive tracers are missing. Yet, because of the large technological and economic impact of this special class of materials, reliable diffusion data and a thorough understanding of diffusion mechanisms are needed. Based on existing knowledge, important unsolved problems in the fields of metal atom, non-metal atom and impurity diffusion in the volume, along grain boundaries and at surfaces, are specified.
Bibliographic Reference: Article: Defect and Diffusion Forum, Vol. 83 (1992) pp. 111-130
Record Number: 199210426 / Last updated on: 1994-12-02
Original language: en
Available languages: en