Erosion, which occurs when solid particles entrained in a fluid stream strike a surface, is a serious problem in many engineering systems, including steam and jet turbines, pipelines, valves etc. Generally resistance to erosion requires a combination of hardness and toughness with latter being dominant parameter mostly achieved by functionally gradient material (FGM). In the present study functionally graded ceramic composite deposits with chromium oxide (Cr2O3) as topcoat and tougher alumina-40%titania (AT40) as backup layer was used for functional evaluation. As-sprayed and post-treated ceramic composite deposits were evaluated through monitoring material removal rate and the acoustic emission signal emitted when exposed to an erosive environment. The eroded surfaces were also analysed using scanning electron microscopy (SEM) to understand the erosion wear mechanism involved. Experimental procedure involved and the results are discussed with suitable illustrations.