Neodymium Magnets (UH Grade)

Neodymium magnets (UH Grade) represent the ultra-high coercivity series. This series of magnets has an extremely high intrinsic coercivity, typically not lower than 1990 kA/m, and maintains stable magnetic performance at elevated temperatures (up to 180°C). They exhibit strong resistance to demagnetization, making them suitable for scenarios that require high magnetic stability.

Definition of Neodymium Magnets (UH Grade)

UH stands for “Ultra High Coercivity,” which is a classification in the intrinsic coercivity category of sintered neodymium iron boron permanent magnets.

Intrinsic Coercivity (Hcj): The UH series typically exhibits intrinsic coercivity greater than 25 kOe, enabling the magnets to maintain performance stability under harsh conditions such as high temperatures and reverse magnetic fields, providing exceptional resistance to demagnetization.

Applicable: They are suitable for applications demanding high stability and temperature resistance, such as motors and sensors operating in high-temperature environments.

Grade Composition: Examples include N35UH, N38UH, etc., where the numbers (e.g., 35, 38) indicate the nominal value of the maximum energy product (BH)max; higher numbers correspond to higher energy products.

Advantages of Neodymium Magnets (UH Grade)

Neodymium magnets (UH grade), classified as ultra-high coercivity series, possess several advantages:

| Strong Resistance to Demagnetization: The UH series has extremely high intrinsic coercivity (Hcj), usually above 1990 kA/m. This means that the magnets can maintain their magnetic performance better in high-temperature, reverse magnetic field, or complex electromagnetic environments, far surpassing ordinary series (such as N and M series). For instance, in high-temperature scenarios (above 120°C) or in the presence of strong reverse magnetic fields, UH grade magnets can still operate stably, making them suitable for applications with stringent stability requirements such as aerospace, military equipment, and other magnetic assemblies and devices.

| Good High-Temperature Stability: The maximum working temperature for the UH series magnets is around 180°C, and some high-end products can operate stably at even higher temperatures. This feature allows them to maintain good magnetic performance in high-temperature environments (such as industrial high-temperature furnaces and near automotive engines), reducing performance degradation caused by temperature variations.

| Stable Magnetic Performance: The remanence (Br) and maximum energy product ((BH)max) of UH grade magnets exhibit good stability at high temperatures. Although their magnetic performance parameters may be slightly lower than some high-energy product series (such as N and M series), their overall performance in high-temperature environments is superior, allowing for stable magnetic force output across a wide temperature range.

Performance of Neodymium Magnets (UH Grade)

		Br				H_cj		H_cb		BH_(Max)
	Grade	mT	mT	kGs	kGs	kA/m	kOe	kA/m	kOe	kJ/m3	MGOe
	Grade	Mim.	Max.	Mim.	Max.	Mim.	Max.	Mim.	Max.	Range	Range
UH	N28UH	1040	1080	10.4	10.8	1990	25	764	9.6	207-231	26-29
	N30UH	1080	1140	10.8	11.4	1990	25	788	9.9	223-247	28-31
	N33UH	1140	1180	11.4	11.8	1990	25	816	10.3	247-271	31-34
	N35UH	1180	1230	11.8	12.3	1990	25	845	10.6	263-287	33-36
	N38UH	1220	1250	12.2	12.5	1990	25	886	11.1	287-310	36-39
	N40UH	1250	1280	12.5	12.8	1990	25	915	11.5	302-326	38-41
	N42UH	1280	1320	12.8	13.2	1990	25	938	11.8	318-342	40-43
	N45UH	1320	1360	13.2	13.6	1911	24	976	12.2	342-366	43-46
	N48UH	1360	1390	13.6	13.9	1911	24	1003	12.6	358-390	45-49
	N50UH	1390	1420	13.9	14.2	1911	24	1019	12.8	374-406	47-51

Applications of Neodymium Magnets (UH Grade)

Neodymium Magnets (UH Grade) are part of the ultra-high coercivity series, characterized by high intrinsic coercivity and good high-temperature stability, mainly applied in the following fields:

| Automotive Motors: Used in drive motors for new energy vehicles, air conditioning compressor motors, etc., maintaining stable performance in high-temperature environments to improve motor efficiency and reliability.

| Industrial Motors: Suitable for motors in wind turbines and industrial automation equipment, meeting high-temperature and high-load working conditions.

| Other High-Temperature Applications: Such as magnetic separation equipment and magnetic force separation devices in high-temperature environments, leveraging their high coercivity and high-temperature stability for efficient separation.