Magnetic properties will change with particle size. For example: reducing particle size decreases the coercive field; depending on how the nanoparticles are prepared superparamagnetism can also appear.

Actually, the size of the nanoparticles and the synthesis method have beneficial or non-beneficial effects on the improvement of the magnetic properties of sintered NdFeB magnets. A certain range of particle size distribution can be found to achieve better magnetic properties.The remanence and maximum energy product of the magnet can generally be improved by removing fine particles, while the coercivity of the magnet can be increased by removing coarse particles. A combination of the different sizes of nanoparticles is needed to obtain a magnet with better performance: remanence Br, coercivity Hc and energy product (BH)max. Please find attached this article for guidance.

Good luck to you.

is there an influence on TC, and thermal properties in reversible range? Can Neodymium magnet be matched to the soft ferrite for compensating its saturation magnetization thermal shift without external Permalloy shunts an pads?

I studied the relation between magnetic properties and particle size. This is paper will help you.

Article Magnetization performance of hard/soft Nd9.6Fe80.3Zr3.7B6.4/...

Ashraf M. Semaida, Thank you very much.

However, I checked your paper and did not find there any thermal properties.

Particularly, reversible change in Hc/Br with heating

Andrey Porokhnyuk, Thank you so much.

In the next paper, we will discuss the thermal and mechanical properties.

Ashraf M. Semaida That is wonderful! Waiting with anticipation.

My goal is making a large-scale plate(disk) neodymium magnet with 1200 oe at the surface reducing to controllable, lets say 1500 Oe at temperature raise by 25C; and coming back after cooling.