reaktívdiffúzió

Reaktívdiffúzió, in English reactive diffusion, is a fundamental process in materials science and chemistry. It describes the simultaneous occurrence of diffusion and chemical reaction within a material. Unlike simple diffusion where a substance moves from an area of high concentration to low concentration, reactive diffusion involves the diffusing species actively participating in a chemical transformation as they move. This can significantly alter the concentration profiles and the overall kinetics of the process.

In many practical applications, reactive diffusion is crucial. For example, in the formation of solid-state reaction products, like the growth of an oxide layer on a metal surface or the formation of intermetallic compounds between two metals in contact, reactive diffusion plays a central role. The rate of growth of these layers is often controlled by the interplay between the diffusion of reactant species through the newly formed phase and the chemical reaction occurring at the interfaces.

The mathematical description of reactive diffusion typically involves coupled partial differential equations that account for both the diffusion flux and the reaction rate. The complexity of these equations depends on the specific reaction mechanism, the number of diffusing species, and the geometry of the system. Understanding reactive diffusion is essential for predicting and controlling the performance and lifespan of materials in various environments, from high-temperature oxidation to catalytic processes.