Japan develops rare-earth-free magnets to avoid dependence on China

Japanese manufacturers are developing technology to make magnets for electric and hybrid vehicle motors without using heavy rare earths, a geopolitically sensitive commodity where China holds a large market share.

Rare earth elements with atomic numbers of 62 and above are classified as heavy rare earths. They are crucial for making high-performance magnets used in electric and hybrid vehicle motors.

However, heavy rare earth elements, used to enhance heat resistance, are largely mined and processed in China.

To mitigate the risk of dependence, Japanese specialty materials makers are investing in magnet technology that does not contain heavy rare earths, to protect auto production from future supply shocks.

Currently, the motors of hybrid and electric vehicles often use high-performance neodymium magnets, a commercial permanent magnet with the strongest magnetic field available.

However, neodymium magnets lose their magnetic properties at high temperatures. To address this, manufacturers mix in small amounts of heavy rare earths – mainly dysprosium and terbium – to maintain performance under heat.

Late last July, Proterial Co., Ltd., formerly Hitachi Metals Ltd., announced the development of a neodymium magnet for electric vehicle (EV) motors.

By strictly controlling impurities, the company has achieved performance suitable for EV engines and is also used for hybrid vehicles.

Meanwhile, Daido Steel has commercialized heavy rare earth-free neodymium magnets for hybrid vehicles.

Daido's proprietary grain refinement process produces much finer crystal grains, which are said to significantly improve heat resistance and overall magnetic properties. Honda Motor was the first to apply these magnets to hybrid vehicles in 2016.

Daido Steel said it is also developing higher-power magnets, with plans to invest 5 billion yen ($33.9 million) in a plant in Nakatsugawa, Gifu Prefecture.

The factory is expected to increase its monthly capacity to 45 tons by 2026 and about 150 tons by fiscal year 2030./.

(TTXVN/Vietnam+)

Source: https://www.vietnamplus.vn/nhat-ban-phat-trien-nam-cham-khong-chua-dat-hiem-de-tranh-phu-thuoc-trung-quoc-post1060327.vnp