Effect of alumina content on microstructures, mechanical, wear and machining behavior of Cu-10Zn nanocomposite prepared by mechanical alloying and hot-pressing

Abstract

In the present research work, novel (Cu-10Zn)100-x – x wt.% Al2O3 (x = 0, 3, 6, 9 & 12) nanocomposites were manufactured by mechanical alloying process followed by vacuum hot-pressing technique. The mechanical properties (sinterability, hardness and compressive strength), wear behavior (coefficient of friction, wear rate and worn surface morphology) and machining behavior (surface roughness and chip thickness) were explained and investigated elaborately. The same compositions of (Cu-10Zn)100-x – x wt.% Al2O3 microcomposites (coarse crystalline matrix alloy reinforced with alumina) were also fabricated and compared with nanocomposites. It was observed that uniform distribution and embedding of nano-alumina in the nanocrystallite (nano-grain) matrix in nanocomposites were achieved which exhibited excellent performances. The (Cu-10Zn)88–12 wt% Al2O3 bulk nanocomposite produced highest compressive strength which was around 9.4 times higher than the same amount of reinforcement of microcomposites. Further, nanocomposites showed lower value of coefficient of friction and surface roughness which means a considerable wear resistance and good surface finish was obtained in nanocomposites.