Microstructure and property characterization of Al-based composites reinforced with CuZrAl particles fabricated by mechanical alloying and spark plasma sintering

摘要

In the present work, CuZrAl metallic glass particles were synthesized by mechanical alloying method. High relative density Al-based composites (ABCs) reinforced with different volume fraction of CuZrAl particles have been fabricated by spark plasma sintering (SPS) technique. The microstructures, mechanical properties and corrosion resistance in seawater solution of the ABCs were investigated. The sintered products are all composed of fcc-Al, Al3Zr and CuAl2 phases. For CuZrAl addition, bright and network precipitates are clearly observed in the Al matrix. On account of the interdiffusion of Al and Cu atoms between matrix and reinforcement, the ABCs present the good interfacial bonding. Compared with SPS-ed pure Al bulk, ABCs possess the excellent mechanical properties. It is mainly ascribed to the second phase strengthening, continuously distributed precipitates, high relative density or bonding interface, and grain refinement strengthening. Thereinto, combined with a degree of plastic strain, the composite with 20 vol% CuZrAl reinforcement reveals the best micro-hardness (290 HV), and the highest yield strength and fracture strength of 408 and 459 MPa, respectively. Moreover, the ABCs bear the better pitting resistance with wide passive region in seawater solution. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.