For the first time in the country, the Bhabha Atomic Research Centre (BARC) has developed a technology for preparing magnetic alloy powders from raw materials found in India to manufacture rare earth magnets. The Indian Rare Earths Limited (IREL) will use the technology to manufacture the magnets.
According to experts, this development is significant as it signals India’s self-reliance in rare earth magnets to meet the country’s needs and for export.
Rare earth magnets are permanent magnets with high energy density, which implies that a small volume of magnet will have high magnetic energy. Rare earth magnets, such as samarium-cobalt, have strategic applications in defence, atomic energy and space, in addition to commercial applications.
India’s reasonably high demand for rare earth magnets for various applications is currently met by imports.
“Rare earth magnets like samarium-cobalt find use in atomic energy, space and defence industries for a variety of strategic and non-strategic applications. These exhibit superior quality in terms of performance ability, device miniaturisation capability and stability at high operating temperatures. These are becoming increasingly indispensable components in high power motors, micro motors, alternators, couplers, bearings, and actuators, which cater to various non-strategic industries. Considering the dual uses of these and the fact that India is a non-signatory to the Non-Proliferation Treaty (NPT), availability of the magnets has been scarce. Accordingly, there is a dire need for making indigenous effort to produce rare earth permanent magnets,” said a BARC official.
Rare earth alloy powders prepared using BARC technology was converted to magnets by the Defence Metallurgical Research Laboratory, Hyderabad.
Magnets of different shapes have been prepared and these have been found at par with imported magnets in terms of magnetic properties.
On Friday, at BARC, the technology was transferred to IREL, which will focus on making it commercially competitive and take it to the grassroots level.
“Industrially, rare earth alloys are produced by melting pure rare earth metals at high temperatures. It is, however, expensive due to high cost of rare earth metals, high melting temperature, and rare earth losses in the process. Moreover, it is obtained as a dense ingot, which requires further crushing and grinding before magnet making. All these processes are energy intensive. On the other hand, the process developed by BARC yields the alloy powders directly from inexpensive oxides at much lower temperature, thereby resulting in lower cost magnets. For the first time, this technology has been developed and scaled up to industrial scale at a very competitive price,” said another official from BARC.
Looking at these indigenous efforts, IREL is considering setting up a plant for production of rare earth permanent magnets for use in strategic sectors.