Properties of Alnico Magnets

Magnetic Properties
Magnetic Properties vs.Temperature
Physical Properties

 

 

 

 

 

 

 

 

 

  Magnetic Properties

Grade Br
(Gauss)
Hc
(Oersteds)
Hci
(Oersteds)
BHmax (MGOe) Max. Op. Temp.
(
C )
Relative Cost by Wt.
5 Cast
12,500
640
640
5.5
540
15
5-7 Cast
13,500
740
740
7.5
540
30
6 Cast
10,500
780
800
3.9
540
20
8 Cast
8,300
1,650
1,650
5.5
540
18
2 Sintered
6,600
550
550
1.4
540
8
5 Sintered
10,800
600
600
3.8
540
10
8 Sintered
7,000
1,900
1,900
5.0
540
10

 

  Magnetic Properties vs.Temperature

Material and Grade

Reversible Temperature Cofficient of Br (% Change /C) Curie Temperature Max. Service Temperature
Near Br
Near Max. Energy Prod.
Near Hc
C
F
C
F
Alnico 2
-0.03
-0.02
-0.02
810
1490
450
840
Alnico 5
-0.02
-0.015
-0.01
860
1580
525
975
Alnico 6
-0.02
-0.015
-0.03
860
1580
525
975
Alnico 8
-0.025
-0.01
-0.01
860
1580
550
1020

 

  Physical Properties

Material and Grade

Density Tensile Strength psi Transverse Modulus of Rupture Hardness
(Rockwell
C )
Coefficient Of Thermal Expansion (Inches x10-6 PerC) Electrical Resistivity(Ohm-cm x 10-6 at 20 C
g/cm3 lbs/in3
Alnico 5, Cast
7.3
0.264
5,400
10,500
50
11.4
47
Alnico 6, Cast
7.3
0.265
23,000
45,000
50
11.4
50
Alnico 8, Cast
7.3
0.262
10,000
30,000
55
11
53
Alnico 2, Sintered
6.8
0.246
65,000
70,000
45
12.4
68
Alnico 5, Sintered
6.9
0.25
50,000
55,000
45
11.3
50
Alnico 8, Sintered
7
0.252
50,000
55,000
45
11
54