2019 Volume 58 Issue 1 Pages 214-217
In this study, we investigated the influence of nickel composition on microstructural evolution and magnetic properties in bulk–type copper–based nano–granular magnetic materials with nickel and cobalt. We prepared six Cu–Ni–Co alloys comprising copper, cobalt and nickel from 0〜25 at.%, particularly to focus on the influence of nickel compositions. TEM observations confirmed the linear arrangements of precipitates along the <100> directions of copper matrix were formed, as seen in copper–based nano–granular magnetic materials. However, we found that the microstructure of cobalt–rich magnetic precipitates changed at the later stage of annealing, depending on the nickel composition. The present study suggested that the coercivity was susceptible to the microstructural factors of the magnetic nanoparticles, while the Curie temperature strongly depended on the composition of the magnetic nanoparticles, but not on the microstructure.
