Strong cylinder ferrite magnets with small holes
1.Introduction
Strong cylinder ferrite magnets with small holes are made of hard ferrites, which have a high coercivity and high remanence after magnetization. These are composed of iron oxide and barium or strontium carbonate. The high coercivity means the materials are very resistant to becoming demagnetized, an essential characteristic for a permanent magnet. They also conduct magnetic flux well and have a high magnetic permeability.
2.Material:
Strontium ferrite, SrFe12O19 (SrO·6Fe2O3), a common material for permanent magnet applications.
Barium ferrite, BaFe12O19 (BaO·6Fe2O3), a common material for permanent magnet applications. Barium ferrites are robust ceramics that are generally stable to moisture and corrosion-resistant. They are used in e.g. subwoofer magnets and as a medium for magnetic recording, e.g. on magnetic stripe cards.
Cobalt ferrite, CoFe2O4 (CoO·Fe2O3), used in some media for magnetic recording.
3.Main features:
1.high working temperature
2.good corrosion resistance
3.high intrinsic coercive force
4.Parameter
Max. Operating Temperature |
°c |
250 |
Hardness |
Hv |
480-580 |
Density |
g/cm3 |
4.8-4.9 |
Relative Recoil Permeability |
μ rec |
1.05-1.20 |
Saturation Field Strength |
kOe |
10 |
Temperature Coefficient of Br |
kA/m |
800 |
Temperature Coefficient of iHc |
%/°c
%/°c |
-0.2
0.3 |
Tensile Strength |
N/mm² |
<100 |
Transverse Rupture |
N/mm² |
300 |
5.Typical Properties:
Ferrite Typical Physical Properties of Chinese Standard |
Item |
Grade |
Remanence:Br |
Coercivity:bHc |
Coercivity:iHc |
Max Energy Product |
Br(mT) |
Br(Gs) |
bHc(kA/m) |
bHc(Oe) |
iHc(kA/m) |
iHc(Oe) |
(BH)max(KJ/m3) |
(BH)max(MGOe) |
Y10 |
Isotropic |
200-235 |
2000-2350 |
125-160 |
1570-2010 |
210-280 |
2640-3520 |
6.5-9.5 |
0.8-1.2 |
Y25 |
Anistropic |
360-400 |
3600-4000 |
135-170 |
1700-2140 |
140-200 |
1760-2510 |
22.5-28.0 |
2.8-3.5 |
Y30 |
Anistropic |
370-400 |
3700-4000 |
175-210 |
2200-2640 |
180-220 |
2260-2770 |
26.0-30.0 |
3.3-3.8 |
Y30BH |
Anistropic |
380-400 |
3800-4000 |
230-275 |
2890-3460 |
235-290 |
2950-3650 |
27.0-32.5 |
3.4-4.1 |
Y33 |
Anistropic |
410-430 |
4100-4300 |
220-250 |
2770-3140 |
225-255 |
2830-3210 |
31.5-35.0 |
4.0-4.4 |
Y35 |
Anistropic |
400-420 |
4000-4200 |
160-190 |
2010-2380 |
165-195 |
2070-2450 |
30.0-33.5 |
3.8-4.2 |
6.Applications:
barium ferrite magnets are now widely applied in speaker, louderspeaker,Ferrite magnets have largely displaced Alnico magnets in these applications.It is a common magnetic material for electromagnetic instrument pickups.
7.Production Flow Diagram
Control of Incoming Goods→Iron Oxide&Barium or Strontium Carbonate →Mixing →Presintering-Calcining →Milling →Add Binder →Granulating →Pressing →Sintering →Grinding →Cleaning →Final Inspection →Magnetising →Finished Production
8.kindly reminder
Dear customer,you know all of our product are customized. So in order to save your time, our quotation is based on your material, size,coating,magnetization direction and quantity. If you could send us drawing which shows the information in need, that will be better.