Emerging Opportunities in Manufacturing Bulk Soft-Magnetic Alloys for Energy Applications: A Review

Abstract

Soft-magnetic alloys exhibit exceptional functional properties that are beneficial for a variety of electromagnetic applications. These alloys are conventionally manufactured into sheet or bar forms using well-established insgot metallurgy practices that involve hot- and cold-working steps. However, recent developments in process metallurgy have unlocked opportunities to directly produce bulk soft-magnetic alloys with improved, and often tailorable, structure–property relationships that are unachievable conventionally. The emergence of unconventional manufacturing routes for soft-magnetic alloys is largely motivated by the need to improve the energy efficiency of electromagnetic devices. In this review, literature that details emerging manufacturing approaches for soft-magnetic alloys is overviewed. This review covers (1) severe plastic deformation, (2) recent advances in melt spinning, (3) powder-based methods, and (4) additive manufacturing. These methods are discussed in comparison with conventional rolling and bar processing. Perspectives and recommended future research directions are also discussed.

Production and Characterization of Nanostructured Powders of Nd2Fe14B and Fe90Al10 by Mechanical Alloying

“…Permanent magnets based on rare earth (RE) elements, such as Nd 2 Fe 14 B, play a fundamental role in current and emerging technologies; they are found in commonly used devices (computers, speakers, smartphones, etc. ), in the development of electric vehicles, and are an indispensable input for the construction of electrical generators capable of producing electrical energy from renewable natural sources such as water (hydroelectric power), wind (wind power) and the sea (wave energy) [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. For this reason, the design of high-performance permanent magnets represents a need at the industrial level [ 1 , 2 , 5 , 6 , 7 ].…”

“…), in the development of electric vehicles, and are an indispensable input for the construction of electrical generators capable of producing electrical energy from renewable natural sources such as water (hydroelectric power), wind (wind power) and the sea (wave energy) [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. For this reason, the design of high-performance permanent magnets represents a need at the industrial level [ 1 , 2 , 5 , 6 , 7 ]. Permanent magnets usually contain large amounts of RE and other elements that are difficult to supply, such as Pr, Sm, Dy, Tb, Nd and Co, most of which are mined in foreign countries such as China, Congo, Russia and the United States [ 1 , 2 , 3 , 4 ].…”

“…Therefore, a huge gap crisis has been generated between the supply and demand of these magnets due to the unavailability of these raw materials and the difficulty in supplying them [ 1 , 2 , 3 ]. Taking into account this problem, recent studies have focused on the search for alternatives to produce magnets with a high energy density (BH)max using the smallest possible amount of rare earths [ 1 , 2 , 5 , 7 , 8 , 9 , 10 ]. Thus, the development of producing a two-phase nanocomposite formed by two magnetic phases, a hard one with high anisotropy (NdFeB or SmCo) coupled with a soft one with high magnetization (Fe, FeSi or FeCo), has gained great relevance in recent years and is considered the new generation of permanent magnets [ 1 , 4 , 7 , 8 , 9 , 10 , 11 ].…”

“…Taking into account this problem, recent studies have focused on the search for alternatives to produce magnets with a high energy density (BH)max using the smallest possible amount of rare earths [ 1 , 2 , 5 , 7 , 8 , 9 , 10 ]. Thus, the development of producing a two-phase nanocomposite formed by two magnetic phases, a hard one with high anisotropy (NdFeB or SmCo) coupled with a soft one with high magnetization (Fe, FeSi or FeCo), has gained great relevance in recent years and is considered the new generation of permanent magnets [ 1 , 4 , 7 , 8 , 9 , 10 , 11 ]. These exchange-coupled magnets average the magnetization and anisotropy of the two constituents [ 8 ].…”

Magnetic Behavior of a Laser Deposited Fe–Ni–Mo Alloy

“…[10] and texturing in the <100> "hard" magnetization direction, both of which can be common in AM processes [23] and can negatively affect coercivity and permeability. [24] AM has also been demonstrated for bulk fabrication of other soft magnetic materials; [17,25] however, the use of these materials in shielding applications is limited due to their lower magnetic permeabilities compared to Fi-80Ni-based alloys. [26] For example, Fe-Si alloys are better suited for use in electric motors because of their high electrical resistivity and resultant low eddy current losses.…”