ISSN 1002-1027　　CN 11-2952/G2

### Phenomenological Theory of Interdiffusion Growth of Solid Phase

CHEN Yongchong1, 2, QI Lu1, ZHANG Yonggang3, CHEN Changqi3

• Received:2005-06-13 Online:2006-03-20 Published:2006-03-20

Abstract: Recently the phenomena of diffusion-induced stresses and strains have been highlighted but the systematic theoretical analysis is still scarce. Traditional theory of chemical diffusion in solid states can not describe the relation of diffusion fluxes and diffusion-induced stresses because the research subject of the traditional theory is the diffusing atom or atomic flux, not the volume unit in the interdiffusion field. For this reason, the concept "flow point" in the interdiffusion field is proposed and the methods of fluid mechanics are applied to construct the phenomenological theory for describing the interdiffusion growth of solid phase. Two types of phase growth, i.e. volume and interface growths, are then mathematically defined and the diffusion-induced stresses and strains related to the two types of phasegrowth are elucidated. Also, the interesting periodic layer formation during solid state reactions is discussed as the result of diffusion-induced stresses.