Studies on structural, mechanical and erosive wear properties of ZA-27 alloy-based micro-nanocomposites

Abstract

Metal matrix nanocomposites represent a relatively new class of material, which is still being extensively investigated. Most of the studies, however, are devoted to aluminium- or magnesium-based nanocomposites. A limited number of studies focus on zinc alloy base nanocomposites, with fewer still concentrating on zinc alloy base micro-nanocomposites. In addition, most of the tribological studies investigate adhesive or abrasive wear resistance, whereas studies of erosive wear resistance lag well behind. It was previously shown that the presence of nanoparticles in ZA-27 alloy-based nanocomposites led to a slight increase in erosive wear resistance. Upon discovering that, the aim became to produce micro-nanocomposites that would retain the positive effect of nanoparticles, while further elevating performance, by combining microparticles with nanoparticles. The ZA-27 alloy-based micro-nanocomposites were reinforced with 3 wt. % Al2O3 microparticles (particle size approx. 36 mu m) and with four different amounts (0.3, 0.5, 0.7 and 1 wt. %) of Al2O3 nanoparticles (particle size 20-30 nm). Tested materials were produced by the compocasting process, with mechanical alloying pre-processing. Solid particle erosive wear testing, with particle impact angle of 90 degrees, showed that all micro-nanocomposites had significantly increased wear resistance in comparison to the reference material.