Mechanical characterisation by nanoindentation of zirconium ion implanted alumina

Polycrystalline alpha-Al2O3 was implanted at 170 keV with doses of 2x10(16), 1x10(17) or 2x10(17) ions/cm(2). The as-implanted samples were then annealed at 1000, 1200 and 1400 degrees C. The mechanical properties, such. as hardness (H) and Young's modulus (E), of these ion-implanted samples were characterized by a depth-sensing low-load indentation technique. The results showed that, with a low dose ion implantation followed by annealing at 1200 degrees C, a significant increase in hardness and elastic modulus were found. For higher doses, where the implantation leads to the amorphisation of the material, the mechanical properties of the implanted alumina were inferior to those of unimplanted alumina.