Minimum amount of nano-sized nickel particles to enhance the strength of alumina

摘要

Previous studies demonstrated that the strength of alumina could be enhanced by incorporating >5 vol. percent nano-sized nickel particles. In the present study, the possibility of using a much smaller amount, <0.5 vol. percent, of nano-sized Ni particles to improve the mechanical properties of Al_2O_3 is explored. As the Ni content is low, the densification of Al_2O_3 is affected little and the Ni inclusions remain small after pressureless sintering at 1600 deg C. The presence of Ni inclusions can refine the matrix grains; the strength of Al_2O_3 matrix is consequently enhanced.