Neodymium Ring Magnet OD5mm x H4mm | Hole 2.5mm | N42UH | High Temperature ≤180ºC | Diametrically magnetized
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Neodymium Ring Magnets
Outside Diameter: 5mm (0.196" in.)
Height: 4mm (0.157" in.)
Inside Diameter: 2.5mm (0.098" in.)
Grade: N42UH
Coating: Nickel (Ni)
Magnetized Direction: Through diametrical/side – 5mm
This small Ring Magnet is manufactured in strong N42 UH Grade Neodymium material for extremely good resistance to heat demagnetisation (up to 180°C) and is also Diametrically magnetised. This direction of magnetisation means the North and South poles are on opposite sides of the curved width dimension (diameter). This direction of magnetisation allows the ring to rotate on a shaft or axle when a magnetic field is introduced. These characteristics are mainly of benefit to those engaged in specialised, hi-tech manufacturing and engineering projects and not very practical for everyday use or general holding applications.They may be of use in science classes for demonstrating magnetic fields or the creation of unconventional artwork, toys or inventions.
Typical Physical Properties
NB: Ranges are indicative for product category, please check individual products for specic values within that range.
Production Flow Diagram
Demagnetization Curves
Surface Treatment
The most common coating for Neodymium magnets is Nickel + Copper + Nickel (Ni + Cu + Ni). This coating offers the magnet relatively good protection from corrosion and passive applications. If the magnet will be exposed to moisture or liquid then consider the use of an organic coating such as Epoxy. A hard wearing coating, Epoxy is suited to applications where the magnet will come under some friction or knocking.
Range and Tolerance
Magnets are readily available in Blocks, Discs, Cylinders & Rings. AMF Magnetics specializes in the supply of short-run prototype magnets including Arc Segments, various magnetic orientations etc. If you need a magnet size that we don't carry in stock, submit a Design-a-Magnet enquiry for a quote on your custom magnet design.
Magnetic Properties
Neodymium magnets are offered in several different grades. The first section N30-54 has an operating temperature of up to 80 degrees. Most of our stock only goes up to N38. The second section, denoted with the "M" prefix after the grade has an operating temperature 100 degrees. After this the grades are "H", "SH", "UH" & "EH". In order for the magnet to withstand a higher operating temperature, during production more of the raw material PrNd is incorporated as these elements have a naturally occurring resistance to high temperatures.
Returns Policy
If you are not entirely satisfied with your purchase, we're here to help.
We have a 30 Day Returns policy at Frenergy Magnets. You may return your item within 30 days of receiving it to receive a refund.
The product/s must be unused and in the same condition you received them in. Please contact us at info@frenergy.com.au to initiate the returns process.
The buyer is responsible for the cost of returning the order.