We have studied in detail the structure formation process in Ag-Cu films in the course of vacuum deposition of the metals, followed by thermal annealing, and compared the hardness values of nanocrystalline Ag, Cu, and Ag-Cu films. Under equivalent deposition conditions, the hardness of the Ag-Cu films pro duced by codeposition of the metals exceeds that of the Ag and Cu films. The high hardness of the mixed phase Ag-Cu films is due to their amorphous-nanocrystalline structure. We have determined the limiting grain size above which plastic deformation follows a dislocation mechanism.

The structural changes induced in an amorphous Fe 78 P 20 Si 2 alloy by heat treatment and lamp pro cessing have been compared using X ray diffraction. The results demonstrate that the main effect of the lamp processing is to increase the crystallization rate. Under nanoindentation conditions that do not lead to crys tallization under the action of a concentrated load (as verified by transmission electron microscopy), we have determined the hardness (8 ± 0.3 GPa) and Young's modulus (130 ± 10 GPa) of the amorphous alloy. Lamp processing conditions have been found that lead to the formation of an amorphous-nanocrystalline compos ite whose hardness is almost twice that of the parent amorphous alloy, without loss of plasticity.

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