Nanostructured Ni/n-Al2O3 Metal Matrix Composites Prepared by Pulsed Electrodeposition

Abstract

Metal matrix composites consisting of nano-Al2O3 with crystallite sizes of 45 nm dispersed in a nanocrystalline nickel matrix with different crystallite sizes were electrochemically deposited by pulsed electroplating from a suspension of nano-corundum particles in different electrolytes. The influences of duty cycle and suspended amount of corundum in the plating bath on the particle content in the deposites were studied. The Al2O3 content in the deposits has been determined by density measurements using a helium pycnometer. The wear resistance and the deformation behavior of the n-Ni/n-Al2O3 metal matrix composites were determined. The addition of Al2O3 tripled the yield stress up to 1500 MPa and doubled the Vicker's hardness and wear resistance in comparison to pure n-nickel.