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Strengthening Mechanism in Consolidated Amorphous Alloys

Published online by Cambridge University Press:  26 February 2011

M. A. Otooni*
Affiliation:
U.S. Army Armament Research, Development and Engineering Center Armament Engineering Directorate, Armaments Technology Division Metallic Materials Branch
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Abstract

Several samples of consolidated amorphous alloys have been studied by using High Resolution Electron Microscopy (HREM), Differential Scanning Calorimetry (DSC), Microdiffraction (MD), and Energy Dispersive X-Ray Diffraction Analysis (EDXD). The phenomenon of plastic deformation at consolidated particulate interfaces has been examined. Two simultaneous processes have been identified occurring at these boundaries, namely, accelerated nucleation and growth of the deformed zone and the the formation of dislocation microstructures (dislocation networks). It has been observed that both type and the density of microstructures depend on the mode of consolidation. Post consolidation processing, annealing, affects density and the directional distribution of defects in the plastic zone. Microstructural examination of the consolidated mass has revealed two major factors important in the strengthening mechanism: (1) presence of a plastically deformed and pressureinduced nucleated zone; (2) presence of a system of dislocation networks in the compacted particulates. Based on these observations, it has been concluded that the stored strain energies in the plastically deformed zones provides the necessary activation energy for dislocation motions from one particulate to the next. These observations have been employed in developing a quasi-quantative model to explain the strengthening mechanism in consolidated amorphous alloys.

Type
Articles
Copyright
Copyright © Materials Research Society 1987

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References

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