Comparison of dysprosium security strategies in Japan for 2010–2030

Dysprosium (Dy) is a strategic rare-earth element with many uses in modern technology and an extremely limited supply. We compared the effectiveness of two different strategies for reducing total demand for Dy in Japan during the period 2010–2030: development of low-Dy REE (NdFeB) magnets and a program to promote recycling of REE magnets. First we performed a substance flow analysis based on a bottom-up estimation of the Dy inventory in Japan. This enabled us to construct a data set for the forecasts of future demand that could be used to model the outcome of strategies for Dy demand at each stage of Dy flow. For the low-Dy magnet development scenario, the reduction in the proportion of Dy in NdFeB magnets ranged from 0.8% to 5% in end-use products. On that of recycling promotion, recycling rates of end-use products ranged from 5% to 30% over the years. A baseline forecast of Dy demand was made using historical data. We found that the strategy of low-Dy magnet development would be much more effective in reducing Dy demand than recycling promotion.