Executive Summary : | The molecular engineering of permanent magnetic materials (PMMs) is essential for the design and development of advanced smart systems and energy efficient conversion devices.1-10 PMMs, due to their ability to retain magnetic flux even in the absence of an external magnetic field or changes in environmental conditions are widely used in energy conversion and harvesting devices, magnetic recording and memory devices, power generation and transmission technologies, microwave communications, and sensors.11-16 Unlike other energy conversion and storage devices such as batteries, the efficiency of PMMs is unaffected by repeated use. The PMMs potential applications are defined by their ability to preserve their magnetic characteristics over time and under varied environment conditions. The strongest well-known anisotropic sintered Nd-Dy-Fe-B-type PMMs are exclusively explored for these purposes.17-20
The limited supply of rare earths has raised concerns among global economies, including the United states, which predicts an uncertain future due to changing geopolitical alliances. Various reports emphasize the relevance of rare earths in alternative energy technologies and consumer electronics. This is based on the assumption that demand for rare-earth products will rise in the future years due to the rapid growth of technological devices.10, 17, 21-24 As a result, PMMs containing critical rare-earth elements are being re-examined across the globe. Many countries are now conducting advanced research on PMMs beyond rare earths.10, 25 The emphasis should be on developing new magnetic materials with enough magnetization to compete with rare-earth-based PMMs. Manufacturing of rare-earth-free PMMs has become a hot topic in recent years.1-10, 26-27 |