What is an Alnico Magnet?
Alnico magnets are permanent magnets known for their reliable magnetic performance, good corrosion resistance and ability to perform well in applications involving elevated temperatures.
Before the development of modern rare-earth magnets, Alnico was one of the strongest permanent magnetic materials available. Today, Alnico magnets remain an important choice for applications including sensors, motors, measuring equipment and industrial machinery.
But what exactly is an Alnico magnet, and when might it be the right choice for your application?
What Are Alnico Magnets Made From?
The name Alnico comes from three of the main elements used to produce the magnetic alloy:
- Aluminium (Al) forms part of the alloy's structure
- Nickel (Ni) contributes to its magnetic properties and stability
- Cobalt (Co) helps provide reliable magnetic performance
Alnico alloys also typically contain iron and may include smaller quantities of other materials depending on the required properties.
The exact composition matters because different Alnico grades can behave differently. Magnet shape, operating environment and the way the magnet will be used should therefore all be considered when selecting one.
How Are Alnico Magnets Made?
Alnico magnets are generally manufactured using either casting or sintering.
Cast Alnico Magnets
Cast Alnico magnets are made by melting the required metals together and pouring the molten alloy into a mould.
Once the material has cooled, it undergoes controlled heat treatment to develop the required magnetic properties. Additional machining may then be used where precise dimensions or particular features are required.
Casting also allows Alnico to be manufactured in a variety of shapes, which can make it useful for specialised industrial applications.
Sintered Alnico Magnets
Sintered Alnico is made using powdered materials rather than pouring molten alloy into a mould.
The material is compressed into shape and heated so that the particles bond together. This method can be useful for producing smaller components or magnets where dimensional consistency is particularly important.
What Are the Key Properties of Alnico Magnets?
Different magnet materials suit different operating conditions. Alnico remains useful because it combines several characteristics that can be valuable in engineering and industrial applications.
Good Performance at Elevated Temperatures
One of Alnico's best-known characteristics is its temperature stability.
While neodymium magnets are known for their exceptional magnetic strength, they are generally more sensitive to heat than other magnet types such as Alnico.
This can make Alnico worth considering for applications where the magnet may regularly encounter elevated or changing temperatures.
However, suitable operating conditions vary according to magnet grade, size, shape and the application itself. A magnet should always be selected using the relevant product data rather than assuming that every Alnico magnet will perform the same way.
Working with heat or unusual operating conditions? Jobmaster Magnets Canada can help assess your application and determine whether a stock Alnico magnet or a custom magnetic solution is more appropriate.
Stable Magnetic Performance
Alnico can provide consistent magnetic performance over long periods when correctly specified and used within suitable operating conditions.
This is particularly useful in applications such as instruments, sensors and equipment where predictable magnetic behaviour is important.
Good Corrosion Resistance
Alnico also offers good natural resistance to corrosion in many environments.
As with any magnetic material, however, the complete operating environment should be considered before deciding whether a particular magnet is suitable.
How Strong Are Alnico Magnets?
Alnico offers useful magnetic performance, but magnet strength should not be considered in isolation.
Neodymium magnets provide greater magnetic force for their size and are often selected when an application needs high holding power within a compact space.
Alnico may be a better fit when factors such as temperature stability, magnetic consistency and the operating environment are more important than achieving the maximum possible magnetic strength.
The right choice therefore depends on what the magnet actually needs to do rather than simply selecting the strongest material available.
What Are Alnico Magnets Used For?
Alnico magnets continue to be used across industrial, technical and commercial environments. Common applications can include:
- Electric motors
- Generators
- Sensors
- Measuring instruments
- Microphones and audio equipment
- Magnetic fixtures
- Laboratory equipment
- Industrial machinery
- Equipment operating in elevated-temperature environments
For example, an engineer designing a compact component where maximum holding force is critical may consider neodymium. An application involving greater heat exposure and a need for stable magnetic behaviour may instead lead them to consider Alnico.
Understanding the conditions in which the magnet will operate is therefore an important part of material selection.
What Types of Alnico Magnets Does Jobmaster Supply?
Jobmaster Magnets Canada stocks a range of Alnico magnets for different applications. This includes Alnico round bar magnets, which provide a cylindrical format suited to technical, industrial and scientific applications where consistent magnetic performance and precise positioning are required.
The wider Alnico range also includes button magnets and other formats designed for different holding, positioning and technical applications.
If a standard magnet does not suit the application, our custom magnet solutions can help. We’ll work with your requirements, including factors such as dimensions, mounting constraints, operating environment and intended use, to determine an appropriate magnetic solution.
Alnico vs Neodymium Magnets
Alnico and neodymium are both permanent magnet materials, but they are suited to different requirements.
Neodymium magnets are known for exceptional magnetic strength and can produce a high holding force from a relatively small magnet. This makes them useful where space is limited or strong magnetic performance is a priority.
Alnico is often considered where temperature stability and consistent magnetic behaviour are particularly important.
Neither material is automatically the better choice. The best option depends on factors such as:
- Required magnetic strength
- Operating temperature
- Available space
- Magnet shape
- Environmental conditions
- Mounting method
- Long-term performance requirements
Looking at these requirements together helps avoid over-specifying a magnet or choosing a material that does not suit the conditions in which it will be used.
When Should You Choose an Alnico Magnet?
An Alnico magnet may be worth considering when:
- The application involves elevated or changing temperatures
- Stable magnetic performance is important
- Good corrosion resistance is beneficial
- The magnet will be used in measuring, sensing or precision equipment
- Maximum magnetic force in the smallest possible space is not the primary requirement
Every application is different, particularly when heat, unusual dimensions or demanding operating environments are involved.
Need Help Choosing the Right Alnico Magnet?
Jobmaster Magnets Canada supplies Alnico magnets, neodymium magnets and other stock magnetic products for commercial, industrial and personal applications across Canada.
If you are unsure whether Alnico is the right material for your project, the Jobmaster team can review your requirements and help you compare the available options.
For non-standard requirements, Jobmaster can also design and manufacture custom magnets around the needs of your application.
Contact Jobmaster Magnets Canada to discuss your application or request a custom quote.