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Properties and atomic structure of amorphous copper

We have studied the properties of nonmagnetic amorphous TE-TL alloys (TE=Ti, Zr, Hf ; TL=Ni, Cu) over a broad concentration range in order to obtain the parameters associated with the electronic and atomic structure and interatomic bonding in pure amorphous Ti, Zr and Hf [1]. This was achieved by extrapolating approximately linear variation of the data for alloys to zero TL content and by comparing the results with these calculated for different crystalline phases of pure TE. Here we show that the same data can also be used to obtain the properties of pure amorphous cooper. This finding is correlated with the validity of the Vegard´s law for atomic volumes in amorphous Ti-Cu and Zr-Cu alloys [2] which extends also to Hf-Cu alloys. Irrespective of TE, the variations of all studied properties of amorphous TE-Cu alloys extrapolate to the same value for amorphous Cu. Depending on a particular property, their values are either close/somewhat below those for crystalline copper, or are close to those of liquid copper. As already noted [3], the electromagnetic properties extrapolate to those of liquid Cu, whereas the electronic density of states, the Debye temperature and the Young´s modulus are close or little lower than those of crystalline Cu. As expected, the microhardness, Hv , of amorphous Cu is much larger than that of crystalline copper. The results obtained are discussed in some detail and their impact on present understanding of amorphous TE-TL alloys emphasized. [1] R. Ristić, E. Babić, D. Pajić, K. Zadro, A. Kuršumović, I.A. Figueroa, H.A. Davies, I. Todd, L.K. Varga, I. Bakonyi, J. Alloys Compd. , 504S (2010) S194-S197 [2] I. Bakonyi, Acta Materialia 53 (2005), 2509-2520 [3] D. Pavuna, Solid State Commun. 54 (1985), 771-774.

Atomic structure; Amorphous copper

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