Subsquent to Ferrite magnets and AlNiCo magnets ,Neodymium magnets as the third generation are the strongest magnets in the world dut to the higher remanence,coercive force,and higher Max energy product, it even reaches 55MGOe, it is called N55.
It is easily formed into varous sizes, and widely used in mini-motors,meters,sensors,sound device,magnetic suspension system,magnetic transmission machine and iatrical apparatus and other applications. It is prone to corrosion in humid environments,usually need surface treatment according to different applications.
However,neodymium also has its disadvantage.
The following table belows shows the difference of neodymium magnets from other magnet material:
According to the different usage temperature、application ,neodymium magnets are classified to many grades, each grade corresponds to different magnetic field,magnetic flux,pull force etc.
If you want magnet to be applied under 80°C, our "N" grade is ok; if you want magnet to be applied under 120°C, our "H" grade is ok...
If you want stronger magnetic field/magnetic flux or pull force, the bigger number of grade,the stronger magnet. Under 80°C，N35
So,the first step of ordering right magnet is to confirm what the operating temperature is ,then confirm the Magnetic Characteristics/Grades.
1. See the diagram to choose what the working temperature you want.
2. After you confirm the working temperature, you need to choose the right grade from the series ones. Generally, the bigger the number ,the stronger the pull force or magnetic field.
Benefit from the better processability ,neodymium blanks can be made to various shapes and sizes.
Block blanks can be cutted to various of different smaller sizes of block shapes :
Cylinder or Rod can be cutted to various of different smaller discs:
Cylinder or Rod can be drilled different sizes of holes firstly,then be cutted to different discs or cylinders:
Neodymium magnets are custom made products ,no matter how many pieces ,even though one piece,which is needed to be made from the first step to the final step ,except that we have the same size&grade&coating of magnets in our inventory by chance.
Different customer has the different demand for magnets, so ,the uniform catalogue is not available by us.
What you need to do is tell us what the sizes you want( we call it the second step)
Available Dimensions and Tolerance
As we know,the Earth acts like a very big, weak magnet -- that's why compasses point north! In this article,we explore a few interesting facts about Earth’s magnetic field, including a few ways to play with it using neodymium magnets.
Usually,magnet have both poles---N pole and S pole. However, with the developing of technology,multipoles were developed, two poles on a side,3 poles,4 poles...12 poles on a side etc.
so, the third step you need to tell us what the Magnetizing Direction is ?
for block magnet, if you want use N or S pole on big sides, the magnetizing direction should be along thickness; if you want to use N or S pole on small sides,the magnetizing direction should be along length or width.
The pictures as follows offer visual effect:
No matter for block shap or cylinder shape,or other shapes of magnets, there is a angle between mechanical axis and magnetic axis, which is called magnetic declination angle.Usually the angle is less than 2°, which is normal and inevitable .The magnetic declination can lower the magnetic field and magnetic flux.
Our company can controll the magnetic declination less than 1° by strict sintering procedure and accurate machining process.
See the diagrammatic drawing as belows:
The last step is to confirm what coating is ?
As the matrix of Neodymium magnet has no resistance to rust, all the neodymium magnets surface treatment.
Ni+Cu+Ni(NiCuNi) coating is widely applied to different application due to its good look and good resistance to rust.
Zinc coating is widely applied to motors,sensors,and speakers.
Passivation coating is widely applied to motors, rotors,sealed environment.
The following is a list and description of available coating options for custom magnets.
Note: Magnets can only be electro-plated before magnetization. if the plating is compromised after magnetization via abrasion or deliberate machining they cannot be re-plated.
How to confirm you receive the good magnets or the magnets are just what you ordered?
We provide all of customers with test reports issued by our QA department.
One is test reports for dimensions , which is easy to be understood.
Another is demagnetization curve, which describes the magnetic property of magnetic material, and it is the most important index to describes magnetic material.
It contains Remanence field(Br), Normal Coercivity(Hcb), Intrinsic Coercivity(Hcj) and Max.Energy Products(B-H)max.
If you only use the pull force or holding force of magnets, it is easy,you do not need to consider the curve, just tell us how much pull force you want.
If you want the magnets to be applied in motor,high temperature(more than 80°C) or other special environment( high temperature&humidity), you need to study and concern the curve carefully!
Here, we list some High Temperature Demagnetization Curve, which describe the magnetic properties under different temperature:
Hast Neodymium Magnets
Hast Neodymium Magnets is one of our advantages.
With the development of scientific research, requirement on the NdFeB application technology becomes higher and higher. We adopt the most advanced technology and equipment to manufacture Hast Neodymium Magnets, which are different from traditional Sintered Neodymium Magnets. Hast Neodymium Magnets have the advantage of low weight loss, high consistency, high temperature resistance, excellent bonding strength, good adhesive affinity etc.
As poor corrosion resistance of Iron-base and Nd-rich grain boundary, NdFeB magnets can't be used until plated. Comparing with the expansion of elevator, wind turbines and permanent motors application, the customers need higher requirement on corrosion resistance of NdFeB magnets. Because the glue cohesiveness of un-plated products is much better than the plated products, Un-plated products will be better in the security. Now there are more and more customers want to use the un-plated magnets.
The Special Manufacturing Technique For Hast Neodymium Magnets:
As one of the most important application, magnetic assemblies are being applied more and more extensive. UPMAG have developed or are developing and innovating plenty of magnetic assemblies, such as synchronous rotor,In-wheel rotor,linear motor,voice coil motor,magnetic formwork system for precast concrete,magnetic lifter,magnetic coupling, water-proof magnets, magnetic pot ,magnetic hooks,magnetic separator etc.
For more details,pls see products.