INDICATION OF DEGREE OF THE MECHANOCHEMICAL ACTIVATION BY OXYGEN DENSITY

The destruction of the crystalline order via external mechanical effec ts, e.g. by intensive grinding, is an important phenomenon of mechanoc hemistry and is denominated by the author as ''structural activation'' . The mechanochemical structural activation is actually a result of tw o opposite processes: one is the destruction of the crystalline struct ure (amorphisation, AM), the other is a densification in the microenvi ronment within the grains or between the amorphous grains and also a c ertain degree recombination. The dynamic balance of the two processes results in the final state of the milling product, which can be assess ed by the measurement of oxygen density. The mechanochemical balance c an be interpreted as the destruction of the structure of crystalline m aterials and is immediately followed by partial densification of high free energy amorphous atomic aggregates to a more stable and denser, a lthough still amorphous, product. The dominance of recombination proce sses of the originally amorphous materials on prolonged milling is dem onstrated.