A dispersion strengthening method for metallic melts that are used to form large articles. The method comprises adding nanophase particles into a molten metallic melt and dispersing the nanophase particles in the metallic melt. The nanophase particles comprising particles with diameters in the range of about 5 nanometers to about 100 nanometers. The step of dispersing the nanophase particles in the metallic melt spaces the particles from each other with an average interparticle spacing (IPS) in a range from about 10 nanometers to about 500 nanometers.