Bulk nanostructured Ni-P alloys: Elaboration from metastable Ni-P nanoparticles by spark plasma sintering; mechanical and magnetic properties

Nano-sized nickel-phosphor powders with an average particles size of 100 nm were elaborated by polyol method and consolidated by spark plasma sintering (SPS) with sintering temperatures between 600 and 650 degrees C. This leads to consolidated materials with grain size lying in the range 179-560 nm. The relationship between the sintering parameters, microstructures and mechanical properties of these dense samples were investigated. The nickel grain sizes increased with increasing sintering temperature and holding time. The obtained samples exhibit Vickers hardness as high as 593 Hv, a modulus of elasticity of about 210 GPa, and a compressive strength of about 1.9 GPa. They have the coercive fields significantly lower (0.9-7 Oe) as the nickel bulk. (C) 2016 Elsevier B.V. All rights reserved.