Temperature
Excellent High-Temperature Performance
Alnico magnets can operate at temperatures up to 450–550°C, far beyond most other permanent magnets, making them ideal for harsh and hot environments.
Alnico Magnets
High-temperature permanent magnets with excellent stability and linearity, widely used in sensors, instruments, audio, and industrial applications.
What are Alnico Magnets?
Alnico magnets are permanent magnets made primarily from Aluminium (Al), Nickel (Ni), Cobalt (Co), iron and small amounts of other elements. They offer strong magnetic performance with outstanding temperature stability and linearity, especially in applications up to 450–550°C.
Available in both cast and sintered forms, Alnico magnets have been trusted for decades in precision instruments, sensors and audio devices where repeatability and stable magnetic fields are critical.
Key Features of Alnico Magnets
Stability
Outstanding Magnetic Linearity
Very low temperature coefficient and good linearity between induction and applied field, widely used in sensors, meters and precision magnetic circuits.
Mechanical
Machinable & Robust
Compared to many brittle rare-earth magnets, Alnico can be machined (turning, milling, drilling) in its non-magnetized state, and offers good mechanical strength.
Design
Flexible Shapes & Circuits
Rods, horseshoes, rings, blocks and complex shapes for customized magnetic circuits, including open-circuit and closed-circuit designs.
Typical Applications
Sensors & Instrumentation
- Position and angle sensors
- Flow meters & industrial instruments
- Permanent magnet generators
Audio & Guitar Pickups
- Electric guitar pickups (Alnico 2 / 3 / 5)
- Studio microphones and speakers
- Professional audio transducers
Automotive & Industrial
- Speed and rotation sensors
- Engine and gearbox sensors
- Industrial control & switching devices
Holding & Magnetic Tools
- Magnetic chucks and clamps
- Lifting and holding fixtures
- Magnetic jigs for machining
Alnico Magnet Grades
We provide a full range of cast and sintered Alnico grades, including Alnico 2, 3, 5, 5DG and 8, suitable for different performance and cost requirements.
| Grade | Type | Br (kGs) | Hcj (kOe) | (BH)max (MGOe) | Max Operating Temp. |
|---|---|---|---|---|---|
| Alnico 2 | Cast | 7.0–7.4 | 1.3–1.8 | 3.0–4.0 | 450°C |
| Alnico 3 | Cast | 6.5–7.2 | 1.5–2.0 | 2.5–3.5 | 450°C |
| Alnico 5 | Cast | 12.0–13.5 kGs (1.2–1.35 T) | 1.6–2.3 | 5.0–6.5 | 450°C |
| Alnico 5DG | Directional | Higher Br along preferred axis | Enhanced linearity | Up to 7.0 | 450°C |
| Alnico 8 | Cast / Sintered | 7.5–9.0 | 4.5–6.0 | 5.5–9.0 | 500–550°C |
| Custom Grades | Other specialized Alnico grades available upon request. | ||||
Tolerances, Magnetization & Surface Options
Standard Tolerances
- Blocks & bars: typically ±0.10 mm
- Rods & cylinders: ±0.05–0.10 mm
- Horseshoes & complex shapes: per drawing
- Tighter tolerances available for precision parts
Magnetization Options
- Axial, longitudinal and transverse magnetization
- Multi-pole magnetization for special sensors
- Matched sets and calibrated magnetic output
- Design support for open/closed magnetic circuits
Surface Finish & Protection
Alnico usually does not require corrosion coating. We offer:
- Ground surfaces for tight dimensions
- Shot-blasted or as-cast surfaces
- Nickel plating or painting on request
Manufacturing & Engineering Capabilities
Cast & Sintered Alnico
- Large and small cast Alnico blocks and shapes
- Sintered Alnico for smaller, complex parts
- Optimized casting for magnetic performance
Custom Magnetic Design
- Design of horseshoe and bar magnets
- Magnetic circuit and fixture design
- Application-specific field shaping
Assembly & Calibration
- Assembly into steel housings and yokes
- Calibrated magnetic output for sensors & meters
- 100% inspection and traceability on request
Alnico Magnets – FAQ
Is Alnico as strong as Neodymium or SmCo?
No. Alnico has lower energy product than NdFeB and SmCo, but it offers much better high-temperature capability and linearity for some applications.
Does Alnico demagnetize easily?
Alnico has relatively low coercivity, meaning it can be partially demagnetized by strong opposing fields or improper handling in open circuit. Correct circuit design and handling are important.
Where is Alnico still the best choice?
Alnico is preferred in high-temperature, high-linearity and precision instrument applications, such as sensors, meters and high-end audio pickups.
Can you supply matched sets for pickups or sensors?
Yes. We can provide matched Alnico magnet sets with controlled flux output, polarity and dimensions for pickups, sensors and instruments.
Looking for Alnico Magnet Solutions?
Share your drawings, magnetic requirements and working conditions. Our engineering team will help you choose the right Alnico grade and design a reliable magnetic solution.