Ion Implantation Metallurgy: A Study of the Composition, Structure and Corrosion behavior of Surface Alloys Formed by Ion Implantation and Ion Beam Mixing.
Abstract
DIGM(Diffusion Induced Grain Boundary Migration) is necessarily a near surface phenomenon, as may be visualized by artificially separating the process into discreet steps (which, it should be emphasized, occur continuously and simutaneously in practice). The first step is the diffusion of a small amount of solute into a stationary grain boundary, Cb, above that in the adjacent matrix. Immediately following this step, the boundary moves sideways by means of some atomic shuffling cross the boundary plane: This deposits the solute from the boundary into the volume of matrix through which it sweeps. After this second step, the concentration of solute in the boundary is restored to its original level, and so, therefore, is the driving force for grain boundary diffusion, assuming that the source concentration remains constant, and that there is no effect of strain in the alloyed region. The process should then continue, if the boundary continues to move in the same direction and and the depth and concentration of the allowed zone should both be related to the grain boundary diffusivity and the grain boundary mobility. Since the ability to control the depth and concentration of an alloyed zone is potentially useful for the purpose of tailing surface properties to service needs, a study of the exact relationships is desirable, however, much of the necessary information is not yet available, and complicated relationships may exist between grain boundary diffusivity and mobility.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1984
- Accession Number
- ADA140713
Entities
People
- A. H. King
- C. R. Clayton
Organizations
- Stony Brook University