Neodymium-Iron-Boron (NdFeB) magnets, renowned for their exceptional magnetic properties, have traditionally dominated industries such as automotive, electronics, and renewable energy. However, their potential applications extend far beyond these conventional domains. This paper explores two emerging frontiers: quantum computing and space exploration. In quantum computing, NdFeB magnets are pivotal for stabilizing qubits and shielding superconducting circuits from electromagnetic interference, enabling longer coherence times and more reliable quantum operations. In space exploration, their high magnetic flux density and compact size make them ideal for simulating microgravity environments, maintaining astronaut health, and powering advanced propulsion systems. By examining recent advancements and case studies, this paper highlights the transformative role of NdFeB magnets in these cutting-edge fields.

Abstract
Neodymium-Iron-Boron (NdFeB) magnets, renowned for their exceptional magnetic properties, are pivotal in modern technologies ranging from electric vehicles to wind turbines. The optimization of their chemical composition—a delicate balance of neodymium (Nd), iron (Fe), boron (B), and rare-earth additives like dysprosium (Dy)—is critical for enhancing performance while reducing costs and environmental impact. Traditional trial-and-error methods for formula development are time-consuming and resource-intensive. This paper explores how machine learning (ML), a cornerstone of materials informatics, can revolutionize the prediction of new NdFeB magnet formulas by leveraging multi-scale data integration, advanced modeling techniques, and interpretability frameworks. We discuss the challenges, methodologies, and recent breakthroughs in this field, culminating in a roadmap for ML-driven materials discovery.

1. Introduction
Neodymium-iron-boron (NdFeB) magnets are the strongest permanent magnets available, widely used in electric vehicles, wind turbines, and high-performance motors. Their exceptional magnetic properties arise from their unique microstructure, particularly the alignment and interaction of magnetic domains—regions where atomic magnetic moments are uniformly oriented. However, domain walls (boundaries between domains) and defects can lead to energy losses, reducing coercivity (resistance to demagnetization) and remanence (residual magnetization).

Microscopic regulation of domain structures—through grain boundary engineering, dopant addition, stress management, and advanced processing techniques—can significantly enhance magnet performance. This article explores how these strategies optimize domain dynamics to achieve higher coercivity, remanence, and energy product (BH)max, enabling next-generation applications.

1. Introduction
Neodymium-iron-boron (NdFeB) magnets are the strongest permanent magnets available, widely used in electric vehicles, wind turbines, and consumer electronics. However, their production relies on rare earth elements (REEs) like neodymium and dysprosium, whose mining generates significant environmental pollution. Recycling scrapped NdFeB magnets is critical to reducing reliance on primary mining, conserving resources, and mitigating environmental harm. This article explores efficient recycling methods and evaluates whether recycled magnets can achieve magnetic properties comparable to virgin materials.

1. Introduction
Neodymium magnets (NdFeB) are indispensable in renewable energy, electric vehicles, and electronics due to their unmatched magnetic strength. However, their production is marred by severe environmental impacts, primarily from rare earth element (REE) mining and waste disposal. This article outlines a comprehensive framework to mitigate these issues through sustainable mining practices, cleaner production technologies, and efficient waste management systems.

1. Introduction
Neodymium magnets, primarily composed of neodymium-iron-boron (NdFeB), are the strongest permanent magnets available, with applications spanning electric motors, medical devices, renewable energy, and consumer electronics. However, their exceptional magnetic properties come with inherent vulnerabilities to environmental stressors such as high temperatures and mechanical impact. This article explores the mechanisms of breakage under these conditions and provides detailed guidelines for safely handling broken magnetic powder to mitigate hazards.

Abstract
The global demand for rare earth permanent magnets, particularly neodymium-iron-boron (NdFeB) magnets, has surged due to their exceptional magnetic properties, which are crucial for applications in electric vehicles, wind turbines, and consumer electronics. However, the supply chain vulnerabilities and environmental concerns associated with rare earth elements have spurred intensive research into non-rare earth alternatives. Among these, iron-nitrogen (Fe-N) compounds, particularly α"-Fe₁₆N₂ and Sm₂Fe₁₇Nₓ (samarium-iron-nitrogen, or Sm-Fe-N), have emerged as promising candidates. This article reviews the latest research progress in Fe-N compounds, evaluates their current performance limitations, and discusses their potential to replace NdFeB magnets in the future.

1. Introduction
Neodymium-Iron-Boron (NdFeB) magnets are renowned for their exceptional magnetic strength, compact size, and high energy product (up to 52 MGOe). However, their high cost, temperature sensitivity, and susceptibility to corrosion limit their suitability in certain applications. This analysis explores scenarios where ferrite or samarium-cobalt (SmCo) magnets can replace NdFeB magnets, comparing their cost and performance across key parameters.

Introduction to Gradient Magnets
Gradient magnets are specialized magnetic devices designed to produce a magnetic field that varies linearly along a specific direction. This spatial variation in the magnetic field, known as a magnetic field gradient, is fundamental to numerous scientific and industrial applications, particularly in magnetic resonance imaging (MRI), material separation, and precision measurement systems. The design of gradient magnets involves careful consideration of magnetic field uniformity, gradient strength, and coil configuration to meet the specific requirements of each application.

Neodymium magnets, particularly those based on the neodymium-iron-boron (NdFeB) system, are renowned for their exceptional magnetic properties, including high remanence (Br) and coercivity (Hci), which contribute to their superior magnetic energy storage capacity. However, the quest to further enhance these properties and push the boundaries of their performance has led researchers to explore advanced processing techniques such as nanocrystallization and heat treatment. This essay delves into the potential of these processes to break through the current upper limits of magnetic energy storage capacity in neodymium magnets.

The price of neodymium-iron-boron (NdFeB) magnets, the strongest commercially available permanent magnets, is influenced by a complex interplay of factors spanning raw material costs, production processes, market dynamics, and policy interventions. Below is a detailed analysis of the key determinants:

What is China's position in the global Ndfeb magnet supply chain? Where do the technological advantages of other countries (such as Japan and the United States) lie?