Journal of Materials Science, Vol.37, No.14, 2909-2916, 2002
Surface repair of porous and damaged alumina bodies using carboxylate-alumoxane nanoparticles
Aqueous solutions of acetate-functionalized alumina nanoparticles (A-alumoxane), with an average particle size of 28 nm, have been used as alumina precursors for the surface infiltration and repair of porous and/or damaged alumina surfaces. SEM and AFM measurements indicate that treatment with a 1 wt% solution results in a reduction of surface roughness from >0.6 mum to approximate to100 nm for surface pores in the 100 nm to 1 mum range. The use of 6 wt% solutions gives better infiltration repair for 50 mum features, but surface cracking is observed. The surface hardness of the porous alumina substrate is increased upon infiltration. No spallation of the surface infiltration layer is observed after indentation measurements and grain dislodgment is overcome.