|
ALNICO MAGNET
|
|
|
|
What's Alnico
Alnico Magnets derive their name from main constituents - Aluminum, Nickel and Cobalt with Iron as base.
Alnico Magnets
Alnico Magnets can be made by both cast and sintered processes. Alnico Magnets have distinct advantages over other varieties of permanent magnets in terms of moderate prices & widest temperature stability. Alnico is very hard and brittle. Machining or drilling can not therefore be accomplished by ordinary methods. Holes are usually cored in at the foundry. Magnets are cast or sintered as closely as possible to required size so that abrasive grinding to finish dimensions and tolerances is minimized.
DIMENSION
- Standard and Customized
Applications of Alnico Magnets
Speakers, Microphones, Telephones, Micro Motors, Relays, Measuring Instruments (Volt Amp, Speed-Meter, Watt-Hour -Meter), Flywheel Generators (Motor-Cycles, Farming Machine), Separators, Sensors, Holding Devices, Controls, Braking Devices, Security Systems , Toys, Etc. |
| Demagnetising and Energy Product Curve
|
Cast Alnico
|
|
Charge preparation (raw ingrediants like Al, Ni, Co, Fe mixed in desired proportion) |
|
|
Melting (charge melted in induction furnace at high temperature) |
|
|
Pouring (molten charge poured into stacks of sand moulds to prepare cast magnets) |
|
|
Cooling (stacks of cast magnets cooled to room temperature) |
|
|
Stack breaking (stacks of cast magnets segregated into individual magnets and feed metal) |
|
|
Cleaning (cast magnets cleaned by shot blasting and sly barreling) |
|
|
Snagging (magnets rough ground to remove flash/surface defects) |
|
|
Heat treatment and Grinding (magnets heat - treated and ground to get close tolerance finish and correct warppage) |
|
|
Inspection magnets inspected for physical and magnetic properties |
|
|
Anti rust treatment (magnets coated with anti rust oil) |
|
|
Packing and Dispatch (magnets packed in cartons and dispatched) |
|
Sintered Alnico
|
|
Powder preparation (raw ingredients like Al, Ni, Co, Fe mixed to form a fine homogenized powder) |
|
|
Pressing (powder pressed into desired shape in a die) |
|
|
Sintering (pressed magnets sintered in hydrogen atmosphere at high temperature) |
|
|
Heat Treatment and Grinding (magnets heat-treated and ground to get close tolerance finish and correct wrappage) |
|
|
Inspection (magnets inspected for physical and magnetic properties) |
|
|
Packing and Dispatch (magnets packed in cartons and dispatched) |
|
MAGNETIC PROPERTIES
|
Cast AlNiCo
|
|
Material
|
Equivalent MMPA Class
|
Br
|
Hcj
|
BHmax
|
Den-sity
|
Temperature Coefficient
|
Curie
Tempe
-rature Tc
|
Working Tempe
-rature Tw
|
|
mT
|
Gs
|
KA/m
|
Oe
|
KJ/m3
|
MGOe
|
g/cm3
|
Near Br %/°C
|
Near Hci %/°C
|
°C
|
°C
|
|
LN9
|
AlNiCo 3
|
680
|
6800
|
30
|
380
|
9.0
|
1.13
|
6.9
|
-0.03
|
-0.02
|
810
|
450
|
|
LN10
|
600
|
6000
|
40
|
500
|
10.0
|
1.20
|
6.9
|
-0.03
|
-0.02
|
810
|
450
|
|
LNG12
|
AlNiCo 2
|
720
|
7200
|
45
|
500
|
12.4
|
1.55
|
7.0
|
-0.03
|
-0.02
|
810
|
450
|
|
LNG13
|
|
700
|
7000
|
48
|
600
|
12.8
|
1.6
|
7.0
|
-0.03
|
-0.02
|
810
|
450
|
|
LNG37
|
AlNiCo5
|
1200
|
12000
|
48
|
600
|
37.0
|
4.65
|
7.3
|
-0.02
|
+0.02
|
860
|
525
|
|
LNG40
|
1250
|
12500
|
48
|
600
|
40.0
|
5.00
|
7.3
|
-0.02
|
+0.02
|
860
|
525
|
|
LNG44
|
1250
|
12500
|
52
|
650
|
44.0
|
5.50
|
7.3
|
-0.02
|
+0.02
|
860
|
525
|
|
LNG52
|
AlNiCo 5DG
|
1300
|
13000
|
56
|
700
|
52.0
|
6.50
|
7.3
|
-0.02
|
+0.02
|
860
|
525
|
|
LNG60
|
AlNiCo 5-7
|
1350
|
13500
|
59
|
740
|
60.0
|
7.5
|
7.3
|
-0.02
|
+0.02
|
860
|
525
|
|
LNGT28
|
AlNiCo 6
|
1000
|
10000
|
58
|
720
|
28.0
|
3.50
|
7.3
|
-0.02
|
+0.03
|
860
|
525
|
|
LNGT36J
|
AlNiCo 8HC
|
700
|
7000
|
140
|
1750
|
36.0
|
4.50
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
LNGT18
|
AlNiCo 8
|
580
|
5800
|
100
|
1250
|
18.0
|
2.2
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
LNGT32
|
AlNiCo 8
|
800
|
8000
|
100
|
1250
|
32.0
|
4.0
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
LNGT40
|
|
800
|
8000
|
110
|
1380
|
40.0
|
5.0
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
LNGT60
|
AlNiCo 9
|
900
|
9000
|
110
|
1380
|
60.0
|
7.50
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
LNGT72
|
1050
|
10500
|
112
|
1400
|
72.0
|
9.00
|
7.3
|
-0.025
|
+0.02
|
860
|
550
|
|
|
Sintered AlNiCo
|
|
Grade
|
Br
|
Hcj
|
Hcb
|
(BH)max
|
Density
|
Temperature
Codfficient %
Change °C
|
Curie
TemperatureTc
|
Remark
|
|
mT
|
Gs
|
KA/m
|
Oe
|
KA/m
|
Oe
|
KJ/m3
|
MGOe
|
g/cm3
|
%/K
|
°C
|
|
FLN8
|
520
|
5200
|
43
|
540
|
40
|
500
|
8-10
|
1.0-1.25
|
6.8
|
-0.022
|
760
|
760
|
|
FLNG12
|
700
|
7000
|
43
|
540
|
40
|
500
|
12-14
|
1.5-1.75
|
7.0
|
-0.014
|
810
|
|
FLNGT14
|
570
|
5700
|
78
|
980
|
76
|
950
|
14-16
|
1.75-2.0
|
7.1
|
-0.020
|
850
|
|
FLNGT18
|
560
|
5600
|
90
|
1130
|
88
|
1100
|
18-22
|
2.25-2.75
|
7.2
|
-0.020
|
850
|
|
FLNG28
|
1050
|
10500
|
47
|
590
|
46
|
580
|
28-33
|
3.5-4.15
|
7.2
|
-0.016
|
850
|
Anisotropy
|
|
FLNG34
|
1100
|
11000
|
51
|
640
|
50
|
630
|
34-38
|
4.3-4.8
|
7.2
|
-0.016
|
890
|
|
FLNGT28
|
1000
|
10000
|
57
|
710
|
56
|
700
|
28-30
|
3.5-3.8
|
7.2
|
-0.020
|
850
|
|
FLNGT31
|
780
|
7800
|
106
|
1130
|
104
|
1300
|
33-36
|
3.9-4.5
|
7.2
|
-0.020
|
850
|
|
FLNG33J
|
650
|
6500
|
150
|
1880
|
136
|
1700
|
31-36
|
4.15-4.5
|
7.2
|
-0.020
|
850
|
|
FLNGT38
|
800
|
8000
|
126
|
1580
|
123
|
1550
|
38-42
|
4.75-5.3
|
7.2
|
-0.020
|
850
|
|
FLNGT42
|
880
|
8800
|
122
|
1530
|
120
|
1500
|
42-48
|
5.3-6.0
|
7.25
|
-0.020
|
850
|
|
Conversion Table
|
|
Quantity
|
Unit C.G.S.
|
Unit S.I.
|
*(S.I.)/(C.G.S.)ratio
|
|
Magnetic flux (Ø)
|
maxwell
|
weber, WB
|
108
|
|
Flux Density B
|
gauss, G
|
tesla, T=Wb/m2
|
104
|
|
Permeability of space (µo)
|
unity
|
henry/meter,H/m
|
102/(4π)
|
|
Intensity of Magnetisation (J)
|
e.m.u.=G/(4)
|
tesla, T=N/Am
|
104/(4π)
|
|
Magnetic field strength (H)
|
108Oersted, Oe
|
ampere/meter,A/m
|
(4π)/103
|
|
Maximum energy product (BHmax)
|
MGOe
|
KJ/m3
|
(4π)/102
|
|
|
|
|
|
|