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Magnetic materials are of great interest due to their unique properties, and both soft and hard magnetic materials are utilised in various applications such as energy harvesting, magnetic recording, and MEMS (Micro-Electro-Mechanical Systems). Reverse pulse plating (RPP) has emerged as a viable fabrication technique to enable the miniaturisation of magnets based on transition metal alloys. In the first part of this review, the advantages in terms of mechanical properties and surface finishing of deposits produced by reverse pulse plating over other techniques were presented. This second part focuses on the state-of-the-art of hard magnetic materials such as Co-Ni-P or Co-Pt alloys and soft magnets like Permalloys (Ni-Fe) deposited through reverse pulse plating, highlighting how this technique can be used to tailor the crystalline structure of the material and reduce residual stresses. Reverse pulse plating was found beneficial in improving properties such as coercivity in soft magnetic materials and magnetic anisotropy in hard magnetic materials, even with increased film thickness. Notably, this technique combines the scalability and affordability of electrodeposition with the ability to produce crack-free, high aspect-ratio magnets while maintaining good magnetic properties. [ABSTRACT FROM AUTHOR]

Magnetic materials always arouse interest due to their unique properties. Both soft and hard magnetic materials are exploited for energy harvesting application, magnetic recording and in MEMS. To boost the applicability of these materials, more versatile fabrication techniques must be developed. Even though the rare earth permanent magnets produced through powder metallurgy can guarantee the highest magnetic performance, this fabrication technique is not practical for the MEMS industry. Moreover, rare earths are very expensive elements. Electrodeposition seems a preferable alternative to chemical or physical vapour deposition techniques to produce both thin and thick magnetic deposits based on transition metal alloys. Among electrodeposition techniques, reverse pulse plating (RPP) guarantees improved mechanical properties and has been found to be beneficial for reducing internal stresses and modifying the internal microstructure and surface morphology as well as for producing thicker layers without observing cracks. Part 1 of the review focuses on how RPP can be used to tailor mechanical properties and morphology to achieve miniaturisation compared to other techniques, particularly in application fields that can benefit from it, such as the microelectronics industry. RPP also modifies magnetic properties by inducing changes in the microstructure. In Part 2 of this review, the state-of-the-art of hard and soft magnetic alloys deposited through RPP will be discussed, examining how this technique can tailor the crystalline structure to influence the coercivity of soft magnetic materials and the magnetic anisotropy of hard magnetic materials. [ABSTRACT FROM AUTHOR]