Rare earths: Hong Kong conference reveals efforts to reduce rare earths in permanent magnets

Rare earths — neodymium magnets

Metal Event’s 15th International Rare Earths Conference took place in Hong Kong between the 7th and 9th November 2018. With increasing industry focus on demand for magnet raw materials, the criticality of neodymium (as well as praseodymium, dysprosium and terbium) was a key topic of discussion, with magnet producers in both China and the rest-of-world speaking of their attempts to lower the use of rare earths and limit exposure to supply risk.

Rare earths account for up to 33% of NdFeB magnets by weight, the vast majority of which is neodymium. Roskill estimates this to be equivalent to 30–32kt of global neodymium consumption in magnets in 2018. With consumption of rare earths in this sector forecast to grow by 4–5%py over the next decade, questions remain over the ability of rare earths supply to meet the industry’s rapidly increasing neodymium demands.

Khan Liu of JL Mag Rare Earths told delegates how grain boundary diffusion technology, which was first developed in Japan to reduce dysprosium, is now used commercially by a number of Chinese companies. He also spoke about the global development of zero-heavy rare earth magnets and the drive to increase their performance to compete with traditional NdFeB magnets. Dysprosium is still vital, however, to NdFeB magnets for use in high temperature applications, including the growing market of electric vehicles.

Elsewhere, the use of lower price cerium is being used to substitute for some of the neodymium. Cerium substitutions can lower magnet raw material costs by 8%, however, once the higher processing costs associated with cerium are included, costs reductions are only around 5%. The use of cerium also reduces coercivity, so additions are limited to low-performance magnets and unsuitable for magnets being used in high-temperature applications.

Magnet recycling is becoming increasingly important to the industry. Internal recycling by the magnet manufacturers and end-of-life recycling now account for at least 25% of global NdFeB magnet output, probably more, said Mr Liu, and could one day increase to over 50%.

Roskill view

As the market tightens and neodymium prices rise, it is possible that automotive manufacturers will consider alternative drive train technologies that do not require rare earth magnets. Delegates spent much time deliberating the exact point at which prices might scare away consumers. Most agreed that the pinch point would come when neodymium approaches US$100/kg, while others thought the auto industry could accept prices as high as US$110/kg.

Although NdFeB magnets offer the highest efficiency and best performance for their size and weight, alternatives—specifically induction motors—offer the potential for better long-term price stability. Tesla was unafraid to use induction motors in its Model X and standard Model 3 designs but has switched to a NdFeB permanent magnet motor for its new Model 3 Long Range vehicle. Although such substitutions can be made in response to changes in raw material costs, it is worth remembering that drive train development takes many years and is unlikely to be changed once established for a particular model. Automotive companies must guard against short-term price rises from early on in a vehicle’s design.

Several delegates spoke about a return to the use of terbium in NdFeB magnets. Terbium had previously been removed by most major manufacturers because of its competitive use in phosphors, but the phosphors market has all but disappeared in the past five years and it is now likely that producers, especially in China, are taking advantage of low-cost terbium stocks. Terbium can be used to increase coercivity in the same way as dysprosium.

During the week of the Metal Events conference, Roskill also travelled to Baotou in Inner Mongolia and met with the leading rare earth producers and industry associations. While the rest of the world is focused on Chinese production quotas for rare earth producers as a potential limiting factor for the industry, the Chinese manufacturers of downstream products appear to be much less concerned about a shortage to meet demand. There is no official data on the availability of Chinese stockpiles of neodymium or dysprosium.

Roskill’s 2018 Rare Earths: Global Industry, Markets & Outlook report will be published in December and include supply, demand and price forecasts out to 2028. Click here to download the brochure and sample pages or to access further information.