Ferrite Magnets

The hard ferrite is manufactured with SrO or BaO and Fe₂O₃ by ceramic process,it is also called ceramic mangets. Because of its cheaper price, and production process is relatively simple, compared with the prices of their products relatively cheap in terms of other magnets. The main raw materials of ferrite magnets is oxide, so, it could not be eroded due to the impact of chemical substances or the environment (except for acid). Therefore, the surface does not need electroplating treatment. It is mainly used in handicrafts, drawing annex, toys, motor, loud speakers.

Sintered Ferrite magnets have excellent corrosion resistance and have normal operating capabilities between -40 oC and +250 oC.

Applications of Ceramic Magnet

·Speaker magnets
·DC brushless motors
·Magnetic Resonance Imaging (MRI)
·DC permanent magnet motors (used in cars)
·Separators (separate ferrous material from
·Used in magnetic assemblies designed for lifting,
Holding,retrieving and separating
·Magnetic Door Catcher
·Instrument and Meters
·Toys
·Arts and crafts

Attributes of Ceramic Magnet
·High intrinsic coercive force
·Available in simple shapes only due to manufacturing process
·Lower service temperature than alnico, greater than rare earth
·Lower energy product than alnico and rare earth magnets

Attributes of Ceramic Magnet

·High intrinsic coercive force
·Available in simple shapes only due to manufacturing process
·Lower service temperature than alnico, greater than rare earth
·Lower energy product than alnico and rare earth magnets

Magnetic Properties of Sintered Ferrite Magnets

National standard

Grade	Value
	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

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

USA standard

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

Europe standard

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

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

Physical Characteristics

Compressive Strength	1.4 x 104 kg/cm2
Required Magnetizing Field	12,000 – 15,000 Oe
Electrical Resistivity	> 104 μ-ohm-cm/cm2
Density	4.7-5.0 g/cm3
Recoil Permeability	1.05 μr
Rev. Temp. Coeff.	-0.20 %/°C