Many customers ask us: Remanence, coercivity, energy product… what do these parameters actually mean? How should you evaluate them when selecting magnets?
Don’t worry—you don’t need to become a magnet expert. We’ll use a simple rubber band slingshot analogy to help you understand these core parameters in just one minute.
The Scenario: Using a Rubber Band as a Slingshot
Imagine you’re using a rubber band as a slingshot, with a small stone placed in the middle. When you release it, the stone flies forward.
A magnet’s performance is very similar to the “elasticity” and “power” of this rubber band.
Five Core Parameters, One Analogy
1. Remanence (Br)
Like how fast the stone flies when released
You pull back the rubber band and let go—how fast does the stone fly out at that moment?
This is like a magnet after being magnetized: when the external magnetic field is removed, how much magnetic strength it retains.
2. Coercivity (Hcb)
Like how hard you must pull to stop the stone
If you don’t want the stone to fly out, you need to hold it back or pull in the opposite direction.
This is similar to applying a reverse magnetic field to cancel the magnet’s magnetism. It represents how much reverse force is needed to neutralize the magnet.
3. Intrinsic Coercivity (Hcj)
Like the force that permanently damages the rubber band
If you pull too hard and the rubber band snaps or deforms, it will never work the same again.
This is like a magnet being exposed to a strong reverse magnetic field—its internal structure is permanently damaged and cannot recover.
4. Maximum Energy Product (BHmax)
Like the total power of the rubber band’s strongest shot
A rubber band with strong elasticity and tension can shoot a stone farther and faster.
This represents the magnet’s overall output capability—the optimal combination of remanence and coercivity.
5. Surface Field
Like the impact force you feel at different distances
If you stand close, the impact is strong; farther away, it becomes weaker.
Surface field refers to the magnetic strength at a specific point on the magnet’s surface, influenced by size, shape, and measurement distance.
How to Choose the Right Magnet Grade
Once you understand these parameters, selecting magnets becomes much easier.
Step 1: Check Magnetic Strength
The numbers in neodymium magnet grades (such as N35, N42, N52) represent the energy product. Higher numbers indicate stronger magnetism.
- General use with sufficient space → N35, N38
- Strong holding force in limited space → N42, N45, N48
- Ultra-compact applications → N50, N52
Step 2: Check Temperature Resistance
The suffix letters (M, H, SH, UH, EH, TH) indicate intrinsic coercivity and temperature resistance.
- Indoor, room temperature → No suffix or M grade
- Heat-generating equipment (e.g., motors) → H or SH
- High-temperature environments → UH, EH, TH
Step 3: Choose the Right Coating
Consider the following:
- Environment: dry or humid, indoor or outdoor, normal or high temperature
- Special requirements: conductivity, welding, adhesive bonding, or appearance
- Product characteristics: holes, micro-size, or thin structures
Still Not Sure? Just Tell Us Your Needs
Simply tell us:
- Where the magnet will be used
- Operating temperature
- Required holding force
- Available space
We’ll handle the rest.
One Sentence to Remember
Grade = Magnetic Strength Number + Temperature Resistance Letter
Choosing a magnet is like choosing a slingshot—you need both strong power and reliable durability.
Contact Us
Still unsure? Contact Dahua’s professional sales team.
You describe your requirements—we provide the best solution.
Dahua Magnetic — China’s Leading Magnetic Manufacturer, Your Most Reliable Magnet Partner!
