Sintered Ferrite Magnets
Hard Ferrite Magnets are manufactured by a die pressing followed by sintering process which allows economic production of components in a varied array of sizes and shapes. Ferrite Magnets have excellent corrosion resistance and have normal operating capabilities between -40 ºC and +250 ºC.
When considering a new design using hard Ferrite Magnets, in order to minimize the potential for manufacturing difficulties and to be more assured of a satisfactory, and perhaps less costly product, one should bear in mind a few rules: 1,) The maximum thickness in the direction of pressing should be approximately one inch, and this dimension (also called the magnetic length) should be less than any other dimension. If greater thickness is needed for a particular application, two or more magnets may be stacked and cemented together. 2,) Whenever possible, magnetic circuits should be designed to accommodate unground dimensional tolerances (except for the thickness, which is normally ground to +/-.005 inch. Additional grinding is usually a significant portion of the total cost. 3,) Slots, steps, or any abrupt change in cross section should be avoided. The arc ends of motor segments should preferably be flat at the outside corner.
Manufactured from oxide materials using powder metallurgical process. Ceramic magnet is most widely used because of its low cost, high-energy, good electric insulation and excellent resistance to demagnetization. The most common type of ceramic magnets are anisotropic strontium, anisotropic barium and isotropic barium magnet.
Our huge range of ceramic magnet can ensure us to supply assortment of goods to choose from,which includes arc segments,ring types discs, blocks, bars and more, in a variety of sizes and shapes. This selection includes all grades, oriented and non-oriented, bi-pole and multi-pole magnets.
Mostly Used national standard - SJ285-77 permanent Ferrite Magnet standard
Grade |
Value(min/typical in our factory) |
|||||||
Br |
Hcb(BHC) |
Hcj(IHC) |
(BH)max |
|||||
MT |
KG |
KA/m |
Koe |
KA/m |
KOe |
Kj/m3 |
MGOe |
|
Y10T(=C1) |
200/218 |
2.00/2.18 |
125/145 |
1.57/1.82 |
210/250 |
2.64/3.14 |
6.5/8.0 |
0.8/1.0 |
Y25 |
360/370 |
3.60/3.70 |
135/150 |
1.70/1.88 |
140/170 |
1.76/2.14 |
22.5/25.3 |
2.8/3.2 |
Y30(=C5) |
380/385 |
3.80/3.85 |
191/210 |
2.40/2.64 |
199/220 |
2.50/2.51 |
26.0/28 |
3.4/3.7 |
Y30BH |
380/390 |
3.80/3.90 |
223/235 |
2.80/2.95 |
231/245 |
2.90/3.08 |
27.0/30.0 |
3.4/3.7 |
Y33 |
410/420 |
4.10/4.20 |
220/235 |
2.77/2.95 |
225/240 |
2.83/3.01 |
31.5/33.0 |
4.0/4.2 |
Y35 |
400/410 |
4.00/4.10 |
175/195 |
2.20/2.45 |
180/200 |
2.26/2.51 |
30.0/32.0 |
3.8/4.0 |
C8(=C8A) |
385/390 |
3.85/3.90 |
235/255 |
2.95/3.20 |
242/265 |
3.05/3.33 |
27.8/30.0 |
3.5/3.7 |
C10 |
400/410 |
4.00/4.10 |
288/300 |
3.62/3.77 |
280/287 |
3.51/3.60 |
30.4/31.9 |
3.8/4.0 |
Chinese standard -sj/T10410 2000 permanent Ferrite Magnet standard
Material |
Br |
HcB |
HcJ |
(BH)max |
||||
mT |
KG |
KA/m |
Oe |
KA/m |
Oe |
Kj/m³ |
MGOe |
|
Y8T |
200~235 |
≥2000 |
125~160 |
≥1570 |
210~280 |
≥2610 |
6.5~9.5 |
≥0.8 |
Y22H |
310~360 |
≥3100 |
220~250 |
≥2770 |
280~320 |
≥3520 |
20.0~24.0 |
≥2.5 |
Y25 |
360~400 |
≥3600 |
135~170 |
≥1700 |
140~200 |
≥1760 |
22.5~28.0 |
≥2.8 |
Y26H-1 |
360~390 |
≥3600 |
220~250 |
≥2512 |
225~255 |
≥2830 |
23.0~28.0 |
≥2.9 |
Y26H-2 |
360-380 |
≥3600 |
263-288 |
≥3300 |
318-350 |
≥4000 |
24.0-28.0 |
≥3.0 |
Y27H |
370~400 |
≥3500 |
225-240 |
≥2830 |
235-260 |
≥2950 |
25.0~29.0 |
≥3.1 |
Y28 |
370-400 |
≥3700 |
175-210 |
≥2200 |
180-220 |
≥2260 |
26.0-30.0 |
≥3.3 |
Y28H-1 |
380-400 |
≥3800 |
240-260 |
≥3020 |
250-280 |
≥3140 |
27.0-30.0 |
≥3.1 |
Y28H-2 |
360-380 |
≥3600 |
271-295 |
≥3400 |
382-405 |
≥1800 |
26.0-30.0 |
≥3.3 |
Y30 |
370~400 |
3.7~4.0 |
175~210 |
2.20~2.64 |
180~220 |
2.26~2.77 |
26.0~30.0 |
3.3~3.8 |
Y30H-1 |
380~400 |
≥3800 |
230-275 |
≥2890 |
235-290 |
≥2950 |
27.0~32.5 |
≥3.4 |
Y30H-2 |
395-415 |
≥3950 |
275-300 |
≥3460 |
310-335 |
≥3900 |
27.0~32.0 |
≥3.4 |
Y32 |
400~420 |
≥4000 |
160~190 |
≥2010 |
165~195 |
≥2070 |
30.0~33.5 |
≥3.8 |
Y32H-1 |
400-420 |
≥4000 |
190-230 |
≥2390 |
230-250 |
≥2890 |
34.5-35.0 |
≥4.0 |
Y32H-2 |
400-440 |
≥4000 |
224-240 |
≥2810 |
230-250 |
≥2890 |
31.0-34.0 |
≥3.9 |
Y33 |
410~430 |
≥4100 |
220~250 |
≥2760 |
225~255 |
≥2830 |
31.5~35.0 |
≥4.0 |
Y33H |
410-430 |
≥4100 |
250-270 |
≥3140 |
250-275 |
≥3140 |
31.5-35.0 |
≥4.0 |
Y34 |
420-440 |
≥4200 |
200-230 |
≥2510 |
205-235 |
≥2580 |
32.5-36.0 |
≥4.1 |
Y35 |
430-450 |
≥4300 |
215-239 |
≥2700 |
217-242 |
≥2730 |
33.1-33.2 |
≥4.2 |
Y36 |
440-450 |
≥4400 |
247-271 |
≥3100 |
250-374 |
≥4400 |
35.1-38.3 |
≥4.4 |
Y38 |
440-460 |
≥4400 |
285-305 |
≥3580 |
294-310 |
≥3690 |
36.6-40.6 |
≥4.6 |
Y40 |
450-460 |
≥4500 |
330-354 |
≥4150 |
340-360 |
≥4270 |
37.6-41.8 |
≥4.7 |
Demagetization Curves of Permanent Ferrite Magnet
USA standard - permanent Ferrite Magnet industry standard of USA
Material |
Br |
HcB |
HcJ |
(BH)max |
||||
mT |
KG |
KA/m |
KOe |
KA/e |
KOe |
kj/m³ |
MGOe |
|
C1 |
230 |
2.3 |
148 |
1.86 |
258 |
3.5 |
8.36 |
1.05 |
C5 |
380 |
3.8 |
191 |
2.4 |
199 |
2.5 |
27 |
3.4 |
C7 |
340 |
3.4 |
258 |
3.23 |
318 |
4.00 |
21.9 |
2.75 |
C8(=C8A) |
385 |
3.85 |
235 |
2.95 |
242 |
3.05 |
27.8 |
3.5 |
C8B |
420 |
4.2 |
232 |
2.913 |
236 |
2.96 |
32.8 |
4.12 |
C9 |
380 |
3.8 |
280 |
3.516 |
320 |
4.01 |
26.4 |
3.32 |
C10 |
400 |
4.0 |
288 |
3.617 |
280 |
3.51 |
30.4 |
3.82 |
C11 |
430 |
4.3 |
200 |
2.512 |
204 |
2.56 |
34.4 |
4.32 |
Japan TDK standard
Grade |
Composition¡¡ |
Br |
Hcb | Hcj |
BH max |
||||||
mT |
kG |
kA/m |
kOe |
kA/m |
kOe |
KJ/m3 |
MGOe |
||||
FB40 |
SrO6Fe2O3 |
410+/-10 |
4.1+/-10 |
234.8+/-11.9 |
2.95+/-0.15 |
238.7+/-15.9 |
3.0+/-0.2 |
31.4+/-1.6 |
3.95+/-0.2 |
||
FB3N |
SrO6Fe2O3 |
395+/-15 |
3.95+/-15 |
234.8+/-11.9 |
2.95+/-0.15 |
238.7+/-15.9 |
3.0+/-0.2 |
28.7+/-2.4 |
3.6+/-0.3 |
||
FB3G |
SrO6Fe2O3 |
375+/-15 |
3.75+/-15 |
254.6+/-15.9 |
3.2+/-0.2 |
270.6+/-19.9 |
3.4+/-0.25 |
25.9+/-2.4 |
3.25+/-0.3 |
||
FB3X |
SrO6Fe2O3 |
375+/-15 |
3.75+/-15 |
234.8+/-11.9 |
2.95+/-0.15 |
238.7+/-15.9 |
3.0+/-0.2 |
25.9+/-2.4 |
3.25+/-0.3 |
||
FB1A |
SrO6Fe2O3 |
220+/-15 |
2.20+/-15 |
159.2+/-15.9 |
2.0+/-0.2 |
258.6+/-19.9 |
3.25+/-0.25 |
8.9+/-1.6 |
1.1+/-0.2 |
||
FB5H |
SrO6Fe2O3 |
405+/-15 |
4.05+/-15 |
298.4+/-11.9 |
3.75+/-0.15 |
322.3+/-11.9 |
4.05+/-0.15 |
31.1+/-1.6 |
3.9+/-0.2 |
||
FB4X |
SrO6Fe2O3 |
420+/-10 |
4.20+/-10 |
234.8+/-11.9 |
2.95+/-0.15 |
238.7+/-15.9 |
3.0+/-0.2 |
33.4+/-1.6 |
4.2+/-0.2 |
||
FB4B |
SrO6Fe2O3 |
400+/-10 |
4.00+/-10 |
254.6+/-11.9 |
3.2+/-0.2 |
262.6+/-19.9 |
3.3+/-0.25 |
30.3+/-1.6 |
3.8+/-0.2 |
||
FB4A |
SrO/BaO6Fe2O3 |
410+/-10 |
4.10+/-10 |
175.1+/-15.9 |
2.2+/-0.2 |
176.7+/-15.9 |
2.22+/-0.2 |
31.8+/-1.6 |
4.0+/-0.2 |
||
FBGN |
SrO6Fe2O3 |
440+/-10 |
4.40+/-10 |
258.6+/-11.9 |
3.25+/-0.15 |
262.6+/-11.9 |
3.3+/-0.15 |
36.7+/-1.6 |
4.6+/-0.2 |
||
FB6B |
SrO6Fe2O3 |
420+/-10 |
4.20+/-10 |
302.4+/-11.9 |
3.8+/-0.15 |
318.3+/-11.9 |
4.0+/-0.15 |
33.4+/-1.6 |
4.2+/-0.2 |
||
FB6H |
SrO6Fe2O3 |
400+/-10 |
4.00+/-10 |
302.4+/-11.9 |
3.8+/-0.15 |
358.1+/-11.9 |
4.5+/-0.15 |
30.3+/-1.6 |
3.8+/-0.2 |
||
FB6E |
SrO6Fe2O3 |
380+/-10 |
3.80+/-10 |
290.5+/-11.9 |
3.65+/-0.15 |
393.9+/-11.9 |
4.95+/-0.15 |
27.5+/-1.6 |
3.45+/-0.2 |
||
FB5N |
SrO6Fe2O3 |
440+/-10 |
4.40+/-10 |
256.8+/-11.9 |
2.85+/-0.15 |
2259.2+/-11.9 |
2.88+/-0.15 |
36.7+/-1.6 |
4.6+/-0.2 |
||
FB5B |
SrO6Fe2O3 |
420+/-10 |
4.20+/-10 |
262.6+/-11.9 |
3.3+/-0.15 |
266.6+/-11.9 |
3.35+/-0.15 |
33.4+/-1.6 |
4.2+/-0.2 |
||
The standard from International Electronics Committee(IEC404-8-1)
Grade |
Allowed Value (min/typical) |
|||||||
Br |
Hcb(BHC) |
Hcj(IHC) |
(BH)max |
|||||
MT |
KG |
KA/m |
KOe |
KA/m |
KOe |
Kj/m³ |
MGOe |
|
HF8/22 |
200/220 |
2.00/2.20 |
125/140 |
1.57/1.76 |
220/230 |
2.76/2.89 |
6.5/6.8 |
0.8/1.1 |
HF20/19 |
320/333 |
3.20/3.33 |
170/190 |
2.14/2.39 |
190/200 |
2.39/2.51 |
20.0/21.0 |
2.5/2.7 |
HF20/28 |
310/325 |
3.10/3.25 |
220/230 |
2.76/2.89 |
280/290 |
3.52/3.64 |
20.0/21.0 |
2.5/2.7 |
HF22/30 |
350/365 |
3.50/3.65 |
255/265 |
3.20/3.33 |
290/300 |
3.64/3.77 |
22.0/23.5 |
2.8/3.0 |
HF24/16 |
350/365 |
3.50/3.65 |
155/175 |
1.95/2.20 |
160/180 |
2.01/2.26 |
24.0/25.5 |
3.0/3.2 |
HF24/23 |
350/365 |
3.50/3.65 |
220/230 |
2.76/2.89 |
230/240 |
2.89/3.01 |
24.0/25.5 |
3.0/3.2 |
HF24/35 |
360/370 |
3.60/3.70 |
260/270 |
3.27/3.39 |
350/360 |
4.40/4.52 |
24.0/25.5 |
3.0/3.2 |
HF26/16 |
370/380 |
3.70/3.80 |
155/175 |
1.95/2.20 |
160/180 |
2.01/2.26 |
26.0/27.0 |
3.2/3.4 |
HF26/18 |
370/380 |
3.70/3.80 |
175/190 |
2.20/2.39 |
180/190 |
2.26/2.39 |
26.0/27.0 |
3.3/3.4 |
HF26/24 |
370/380 |
3.70/3.80 |
230/240 |
2.89/3.01 |
240/250 |
3.01/3.14 |
26.0/27.0 |
3.3/3.4 |
HF26/26 |
370/380 |
3.70/3.80 |
230/240 |
2.89/3.01 |
260/270 |
3.27/3.39 |
26.0/27.0 |
3.3/3.4 |
HF26/30 |
385/395 |
3.85/3.95 |
260/270 |
3.27/3.39 |
300/310 |
3.77/3.89 |
26.0/27.0 |
3.3/3.4 |
HF28/26 |
385/395 |
3.85/3.95 |
250/265 |
3.14/3.33 |
260/275 |
3.27/3.45 |
28.0/30.0 |
3.5/3.8 |
HF28/28 |
385/395 |
3.85/3.95 |
260/270 |
3.27/3.39 |
280/290 |
3.50/3.60 |
28.0/30.0 |
3.5/3.8 |
HF30/26 |
395/405 |
3.95/4.05 |
250/260 |
3.14/3.33 |
260/270 |
3.27/3.39 |
30.0/31.5 |
3.8/3.9 |
HF32/17 |
410/420 |
4.10/4.20 |
160/180 |
2.01/2.26 |
165/175 |
2.07/2.20 |
32.0/33.0 |
4.0/4.1 |
HF32/22 |
410/420 |
4.10/4.20 |
215/225 |
2.70/2.83 |
220/230 |
2.76/2.89 |
32.0/33.0 |
4.0/4.1 |
HF32/25 |
410/420 |
4.10/4.20 |
240/250 |
3.01/3.14 |
250/260 |
3.14/3.27 |
32.0/33.0 |
4.0/4.1 |
Physical property of hard ferrite mangets
Parameters |
Mark |
Unit |
Value |
Recoil Permeability |
Urce |
- |
1.05-1.3 |
Curie temperture |
Tc |
0C |
460 |
The temperature of Br |
0C-1 |
-0.2% |
|
The temperature of Hcj |
0C-1 |
0.2-0.5% |
|
Density |
D |
g/cm3 |
4.5-5.1 |
Resistivity |
P |
≥104 |
|
The coefficient of linear expansion |
0C-1 |
7-15x10-6 |
|
Hardness |
HV |
- |
480-580 |
Inspection standard for permanent magnet
- When the permanent magnet is not supplied with specific size and shape, the properties of material should be tested. The test standard is as per GB/T3217-95permanent magnet (hard magnet) material test trial method,GJB2453-95rare earth permanent magnet material general criterion and relevant enterprise standard. GB/T3217 stipulated the test method. Enterprise standard stipulated the test process and sampling method.
- When the permanent magnet is supplied with specific size and shape, the properties of the magnetic component should be tested. The properties of the material are only tested for reference.
- For different permanent magnetic components, the test parameters and test methods are different. For magnetic ring, the test parameter is diametric flux density. For magnetic segment and block, the parameters can be surface field, magnetic flux etc. The magnetic flux is better.A digital tesla meter can test diametric flux density With a transverse sensor. Magnetic flux can be tested by permanent magnet tesla meter and Helmholtz coil.For more information about the international standard, you may turn to the following reference:
IEC 404-5(1982) magnetic material Part 5:test measure for hard magnet(permanent magnet) material properties.
JISC 2501-1989 Test method for magnetic material(Japan) - When the permanent magnet is supplied as magnetic assembly or component,the properties of the magnetic assembly or component should be tested. The buyer and seller will negotiate and decide the specific test method with each other.
- Unless specified by the user, we will adopt standard sampling method for the final test of the permanent magnet.