Interface reaction control

Figure 1-12 Control mechanisms of mineral dissolution in aqueous solutions. Data are from Berner (1978). A straight line is drawn to separate transport control and interface reaction control although there is no theoretical basis for whether the boundary should be linear. Almost without exception, those with transport control lie above a straight line, and those with interface reaction control lie below the line. The only significant departure from the rule is the dissolution of PbS04 (cross in the figure) that lies inside the region for the interface reaction control, but is actually controlled by both interface reaction and mass transport.

Interface reaction control 1 2 Lattice/grain boundary... 

Ashby, M. F., On interface-reaction control of Nabarro-Herring creep and sintering, Scripta MetalL, 3, 837—42, 1969. 

Figure 15.2. Schematic of solute concentration gradient in a matrix between two particles with different size 0 and 02 (a) diffusion control and (b) interface-reaction control.

Assuming that the reaction (atom attachment and detachment) at the grain interface is linearly proportional to its driving force, Wagner derived a kinetic equation of interface-reaction-controlled grain growth and a stationary size distribution of grains. This assumption is questionable (see Section 15.2.3) and... 

Figure 15.5. Variation of particle growth rate do/dt for interface reaction-controlled growth (Eq. (15.18)).

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