LAUSR

Abstract The uniform dispersion of carbon nanotubes (CNTs) is usually accompanied by severe grain refinement of Al matrix, which leads to the low ductility of CNT/Al alloy composites. To accommodate this dilemma, a flake powder metallurgy route via elemental alloying was proposed to fabricate CNT/Al-Zn-Mg-Cu composites with improved ductility and high strength. CNT/Al flake powders were firstly obtained by ball milling at a low speed to achieve uniform dispersed of CNTs, and then milled with Zn, Mg and Cu elemental flake powders at a high speed to achieve lamellar CNT/Al-Zn-Mg-Cu particles, which were consolidated and homogenized to obtain bulk CNT/Al-Zn-Mg-Cu composites. Compared with the CNT/AA7075 counterparts fabricated by directly using CNTs and atomized AA7075 powders, the CNT/Al-Zn-Mg-Cu composites exhibited improved ductility with high modulus and strength, due to the well-protected and uniformly aligned CNTs, and good dislocation storage capability of the elongated ultrafine grains.