«Nanocomposites and nanomaterials»

Structure of Al-Cu/C nanocomposites synthesized by mechanical alloying of elemental powders

Matvienko Ya.I.1, Rud A.D. 1, Polishchuk S.S.1, Fesenko O.M.2, Yaremkevich A. D.2, Trachevski V.V.3, Khyzhun O.Y.4
1 G. V. Kurdyumov Institute for Metal Physics of the N.A.S. of Ukraine,
  Academician Vernadsky Boulevard, 36, 03142 Kyiv, Ukraine 
E-mail: yanamatv18@gmail.com
2 Institute of Physics of the N.A.S. of Ukraine,
  Nauki Ave., 46, 03680 Kyiv, Ukraine
3 Technical Center of N.A.S. of Ukraine,
  Pokrovskaya str. 13, 04070 Kyiv, Ukraine
4 Institute for Problems of Materials Science of N.A.S. of Ukraine,
  Krjijanovsky str. 3, 03142 Kyiv, Ukraine

	It was reported that mechanical alloying (MA) of eutectic Al – 33 wt. % Cu powder mixtures without and with  5 wt. % of graphite additives leads to the formation of non-equilibrium phases and supersaturated solid solutions, which have an influence on the mechanical properties of powder nanocomposites [1, 2].
	The present work studies the effect of Cu content (33 and 80 wt. %) on the structure of Al – Cu/ 5 wt. % C nanocomposites prepared using MA of elemental powders Al, Cu and graphite with their subsequent annealing. In both cases, MA up to 8 hours leads to the change of the graphite additives crystalline structure into amorphous one and the formation of disordered bcc Al4Cu9 phase. Moreover, milling of the powders Al – 33 wt. % Cu/ 5 wt. % C from 2 to 8 hours results in the formation of a non-stoichiometric Al2Cu1–x phase (0.012 < x < 0.059) besides bcc Al4Cu9 phase. Annealing at 500 °C of such nanocomposites leads to the formation of the phase composition close to equilibrium, as well as Al4C3 carbide.

1.	Matvienko Y., Rud A., Polishchuk S. et al. Effect of graphite additives on solid-state reactions in eutectic Al–Cu powder mixtures during high-energy ball milling // Appl Nanosci.- 2019.
2.	Ya. I. Matvienko, A. D. Rud, S. S. Polishchuk et al. Phase Transformations during mechanical alloying of powders with eutectic composition of Al–Cu and Al–Cu/C systems and their effect on the structure and mechanical properties of the composites // Metallofiz. Noveishie Tekhnol.- 2019.- 41, N11-P. 1519 – 1538.