Atomic-scale structural evolution in amorphous Nd9Fe85B6 subjected to severe plastic deformation at room temperature

Wei Li; Xiaohong Li; Defeng Guo; Kiminori Sato; Gunderov, Dmitry V.; Stolyarov, Vladimir V.; Xiangyi Zhang
June 2009
Applied Physics Letters;6/8/2009, Vol. 94 Issue 23, p231904
Academic Journal
Understanding the deformation-induced nanocrystallization in amorphous alloys at room temperature is proved to be a great challenge. In the present study, the formation of vacancy-type defects richly surrounded with Fe atoms in amorphous Nd9Fe85B6 subjected to room-temperature high-pressure torsion deformation is directly evidenced by positron lifetime measurements combined with a coincident Doppler broadening measurement of the positron-electron annihilation photons. This demonstrates a direct experimental evidence for shear inducing the enrichment of Fe atoms in the deformed amorphous alloy. These results presented here are of importance for understanding the deformation-induced nanocrystallization and for the technique development of nanocrystalline materials.


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