Characterization Of Cerment Composite Coating Al2O3-Ni System

Abstract

This paper report on the possibility used new technique method by thermal spray coating to produce ceramic-metal coating of nano Al2O3-30%Wt. Ni samples. In this process nano crystalline cermet powders with grain size below 50nm were obtained by mechanical alloying. The steel substrates were degreased and grit blasted with SiC particles to get a mean roughness of 5µm. Experimentally the coating used under the best spraying parameters were deposited on steel substrate with thickness around 1.85mm. This powder and thick coating layers have been characterized by using XRD, SEM, EdS and hardness techniques. The X-ray results show that cerment coating consists a lot of phases such as ɤ-Ni, α-Al2O3 and ɤ-Al2O3 phases. The results also found that the wear resistance is superior, under high load conditions. The improved wear is attributed to the higher values of hardness. Results also show that Nickel was attractive for achieving good self-bonding with ceramic Al2O3 particles for all cerment samples.