Will there be new types of magnets in the future that could replace AlNiCo magnet? What is the trend?

AlNiCo (aluminum-nickel-cobalt) magnets, once the cornerstone of permanent magnet technology, now face unprecedented substitution pressure from emerging materials. This paper systematically analyzes the limitations of AlNiCo magnets in cost, performance, and application scenarios, and explores the replacement potential of five emerging magnetic materials: high-temperature superconductors, Mn-Al alloys, fourth-generation rare-earth magnets, FeCrCo alloys, and altermagnets. Through comparative analysis of magnetic properties, cost structures, and industrialization progress, it reveals that high-temperature superconductors and Mn-Al alloys are most likely to achieve large-scale substitution in the medium to long term, while fourth-generation rare-earth magnets and FeCrCo alloys will compete in niche markets. The paper concludes with strategic recommendations for the magnetic material industry to navigate this transformative period.

1. Introduction

Since its invention in the 1930s, AlNiCo magnets have dominated high-temperature permanent magnet applications due to their exceptional thermal stability (working temperature up to 550°C) and minimal magnetic flux decay (temperature coefficient of -0.02%/°C). However, the material's inherent limitations—high cobalt content (12-28% Co), complex manufacturing process (requiring directional solidification), and relatively low magnetic energy product (3.5-5.5 MGOe)—have become increasingly apparent in the context of modern industrial requirements.

The global magnetic material market is undergoing radical restructuring. By 2025, the rare-earth magnet sector (NdFeB and SmCo) will account for 68% of market value, while traditional non-rare-earth magnets (AlNiCo and ferrite) will shrink to 22%. This shift is driven by three forces: 1) cost pressures from fluctuating rare-earth prices, 2) performance demands from electric vehicles and renewable energy systems, and 3) technological breakthroughs in alternative materials. Understanding these dynamics is crucial for predicting AlNiCo's future trajectory.

2. Limitations of AlNiCo Magnets in Modern Applications

2.1 Cost Structure Vulnerabilities

AlNiCo's cost composition reveals systemic vulnerabilities:

• Raw material costs: Cobalt prices surged from 30/kgin2020to70/kg in 2025, directly impacting AlNiCo production costs. A typical AlNiCo 5 magnet contains 24% cobalt, making raw materials account for 65-70% of total cost.
• Processing costs: Directional solidification requires precise temperature control (±1°C) and long production cycles (72-120 hours per batch), resulting in processing costs 3-5 times higher than sintered NdFeB magnets.
• Yield rate challenges: The brittle nature of AlNiCo leads to a 15-20% machining loss rate during grinding and cutting, further inflating costs.

2.2 Performance Bottlenecks

In high-performance applications, AlNiCo faces critical limitations:

• Magnetic energy product: The maximum (BH)max of 5.5 MGOe is significantly lower than NdFeB's 55 MGOe and even inferior to Mn-Al alloys' 10.8 MGOe (theoretical value).
• Coercivity limitations: AlNiCo 9's coercivity of 1,800 Oe is insufficient for modern motor applications requiring >5,000 Oe to resist demagnetization from armature reaction.
• Shape complexity: The casting process restricts AlNiCo to simple geometries, whereas NdFeB can be molded into intricate shapes via injection molding.

2.3 Application-Specific Challenges

• Automotive sector: The shift to traction motors in electric vehicles has reduced AlNiCo usage from 12% of vehicle magnets in 2015 to 3% in 2025, as NdFeB offers 3× higher torque density.
• Consumer electronics: The miniaturization trend demands magnets with (BH)max >20 MGOe, far exceeding AlNiCo's capabilities.
• Aerospace: While AlNiCo remains dominant in sensor applications (65% market share) due to its radiation resistance, this niche is shrinking as fiber-optic sensors gain traction.

3. Emerging Magnetic Materials with Substitution Potential

3.1 High-Temperature Superconductors (HTS)

Technological Breakthroughs:

• Material advancements: Second-generation REBCO (Rare-Earth Barium Copper Oxide) tapes achieved 1,000 km/year production capacity in China in 2025, with costs dropping to 241/m(from359/m in 2022).
• Magnetic field strength: The 14T HTS magnet developed by CAS Institute of Electrical Engineering surpasses Nb3Sn's 13T limit, enabling compact fusion reactors.
• Thermal stability: YBCO tapes maintain superconductivity at 77K (liquid nitrogen temperature), reducing cooling costs by 90% compared to NbTi (4.2K liquid helium).

Substitution Analysis:

• Energy sector: HTS magnets are replacing NdFeB in grid-scale superconducting magnetic energy storage (SMES) systems, with a 500-ton substitution in China's CFETR project.
• Transportation: Shanghai Maglev's HTS motor achieves 600 km/h speeds with 30% lower energy consumption than conventional motors.
• Market projection: The global HTS market is expected to reach $18 billion by 2030, with China holding 35% share through complete industrial chain localization.

3.2 Mn-Al Alloys

Technological Breakthroughs:

• Magnetic properties: Theoretical (BH)max of 10.8 MGOe approaches ferrite's upper limit, with Toyota achieving 80 kJ/m³ in practical applications.
• Cost advantage: Raw material costs are 40% lower than AlNiCo due to the absence of cobalt and nickel.
• Processing innovations: Shanghai Steel Research Institute's hot extrusion process produces magnets with diameters >10mm, overcoming previous size limitations.

Substitution Analysis:

• Automotive: Toyota's Mn-Al door lock motors reduce costs by 25% while maintaining 10-year durability at 85°C.
• Consumer electronics: Mn-Al speakers in Xiaomi's 2025 flagship phone deliver 105dB sensitivity at 1W/1m, matching AlNiCo performance.
• Market projection: Global Mn-Al production capacity will reach 2,000 tons by 2027, capturing 8% of the non-rare-earth magnet market.

3.3 Fourth-Generation Rare-Earth Magnets

Technological Breakthroughs:

• SmFeN materials: Hitachi Metal's SmFeN magnets achieve 50 MGOe (BH)max and 3× better corrosion resistance than NdFeB, though nitrogenation yield remains below 50%.
• FePt/FeCo core-shell structures: Laboratory samples reach 35 MGOe without rare earths, but scaling requires $500 million in new equipment.
• Crystal boundary diffusion (GBD): Baotou Rare Earth's GBD technology reduces dysprosium usage by 70% while maintaining 200°C thermal stability.

Substitution Analysis:

• Robotics: SmFeN's 45 MGOe at 5cm³ volume meets the stringent requirements of humanoid robot joint motors.
• Aerospace: GBD-treated NdFeB magnets power the Long March 9 rocket's attitude control system, withstanding 300g vibrations.
• Market projection: Fourth-generation magnets will capture 15% of the high-end market by 2030, but cost remains 3× higher than conventional NdFeB.

3.4 FeCrCo Alloys

Technological Breakthroughs:

• Mechanical properties: FeCrCo's 1,200 MPa tensile strength enables production of 0.1mm thick magnetic foils for micro-motors.
• Cost optimization: Beijing Institute of Technology's vacuum induction melting process reduces processing costs by 20% through precise temperature control (±5°C).
• Shape precision: CNC machining yields 98.5%合格率 for complex geometries, compared to 75% for AlNiCo.

Substitution Analysis:

• Medical devices: FeCrCo stents maintain 1.2T remanence after 10 years of implantation, outperforming AlNiCo's 0.8T decay.
• Precision instruments: The 0.01° angular accuracy of FeCrCo compasses in drones reduces navigation errors by 40%.
• Market projection: Global FeCrCo demand will grow at 8% CAGR through 2030, driven by 5G base station antenna applications.

3.5 Altermagnets

Technological Breakthroughs:

• Magnetic behavior: Organic altermagnet crystals demonstrate 100% spin polarization at room temperature, enabling 10× higher magneto-optical effects than conventional materials.
• Optical integration: The 0.1° Kerr rotation angle allows integration with silicon photonics for on-chip magnetic sensors.
• Flexibility: Polyimide-based altermagnet films withstand 10,000 bending cycles without performance degradation.

Substitution Analysis:

• Data storage: Altermagnet-based MRAM achieves 1ns switching times and 10^15 endurance cycles, surpassing HDD and SSD technologies.
• Quantum computing: The 99.99% spin purity enables error rates below 10^-6 in topological qubit operations.
• Market projection: Altermagnet research funding will exceed $500 million annually by 2027, with commercial products expected after 2030.

4. Comparative Analysis of Substitution Potential

Key Findings:

1. HTS magnets offer the most comprehensive substitution potential but require breakthroughs in cost reduction (target: $50/m by 2030).
2. Mn-Al alloys are positioned to capture AlNiCo's mid-range market (1-10 MGOe) through cost and processing advantages.
3. FeCrCo alloys will dominate precision machining applications where AlNiCo's brittleness is problematic.
4. Altermagnets represent a long-term disruptive threat but remain in the research phase until 2030.

5. Industry Response Strategies

5.1 For AlNiCo Manufacturers

• Niche specialization: Focus on high-reliability sensors (e.g., oil exploration) where AlNiCo's 50-year lifespan is irreplaceable.
• Hybrid solutions: Develop AlNiCo-HTS composite magnets for fusion reactor first walls, combining thermal stability with high fields.
• Cost reduction: Implement AI-driven process optimization to reduce directional solidification cycle times by 30%.

5.2 For Emerging Material Developers

• HTS: Prioritize cryogenic system integration to address the "last mile" cooling challenge in medical MRI applications.
• Mn-Al: Collaborate with automakers to establish AEC-Q200 qualification standards for automotive-grade magnets.
• Altermagnet: Partner with semiconductor foundries to develop 300mm wafer-scale fabrication processes.

5.3 For End Users

• Dual sourcing: Maintain AlNiCo supply chains while qualifying Mn-Al alternatives for non-critical applications.
• Design flexibility: Adopt modular magnet architectures to facilitate future upgrades to HTS or altermagnet technologies.
• Lifecycle analysis: Evaluate total cost of ownership (TCO) beyond initial material costs, incorporating energy efficiency and maintenance factors.

6. Conclusion

The magnetic material landscape is undergoing its most profound transformation since the invention of NdFeB in 1982. While AlNiCo will retain niche applications in high-temperature sensors and aerospace actuators, its dominance in mainstream markets is irretrievably declining. The substitution race is being won by materials that balance performance, cost, and manufacturability:

1. Short term (2025-2027): Mn-Al alloys will capture 15% of AlNiCo's automotive and consumer electronics market through cost-performance parity.
2. Medium term (2028-2032): HTS magnets will displace 50% of NdFeB in grid energy storage and fusion applications, creating indirect substitution pressure on AlNiCo.
3. Long term (2033+): Altermagnets may redefine magnetic storage and quantum computing, though their impact on traditional magnet markets will be limited.

For the magnetic material industry, the path forward requires three strategic pillars: 1) accelerating cost reductions in emerging technologies, 2) developing application-specific material formulations, and 3) fostering ecosystem collaborations across the value chain. The companies that master this transition will shape the $120 billion magnetic material market of 2040, while those clinging to legacy technologies risk obsolescence.