Mechanical removal of the ILM was performed under mercury vapor endoillumination (Photon II™, Synergetics™, Inc. O'Fallon, MO/USA) in combination with a widefield diffusion light pipe (56.21.23P, Synergetics™, Inc. O'Fallon, MO/USA).
In order to investigate different pipe diffusion behaviors with different diffusing elements, diffusion behaviors of Cr and Ti were studied.
Assuming that this phenomenon is sufficiently pronounced to represent the well-known pipe diffusion theory, the calculated diffusion mean free path of C and Mn at 573 K are 3.65 μm and 53 nm, respectively39.
Small individual SFT are formed at the highest temperatures, attesting to short-range pipe diffusion.
The governing equation of chloride diffusion into RC pipe pile is described and solved analytically by using the Bessel functions.
It is reasonably concluded that the pipe diffusion of solute atoms along the dislocation core is responsible for DSA.
Several metallurgical mechanisms are discussed and confronted with the experimental results: dislocations dragging, pipe diffusion, dislocation collection/diffusion and acceleration by excess vacancies.
The behavior of Cr was similar to that of 18O, examined previously, in that their activation energies for lattice and pipe diffusion were similar.
The model appears to resolve a previously reported dilemma that the time exponent suggests pipe diffusion but the kinetics associated with the triple boundary is too slow.
Thus, the absolutely low temperature dependence of Ti pipe diffusion in sapphire may not be because of the enhanced migration of Ti along dislocations but because of other effects, such as the segregation of Ti or Ti clustering at dislocations.
