WISCO CHINA
2013 version
General Introduction of Cold-rolled Electrical Steel
At present, WISCO has a 1.70 million tons
annual capacity on cold-rolled electrical steel,
among which oriented electrical steel occupies
0.40 million (including 0.17 million tons of
high permeability grain-oriented steel, 0.23
million tons of conventional oriented electrical
steel), 1.30 million tons of non-oriented
electrical steel.
Characteristics of Cold-rolled Electrical Steel
ƒ Magnetic Property：
Low core loss and high permeability,
especially for HIB
ƒ Shape ： Transverse
and
longitudinal thickness differences
are small. The lamination or
stacking factors are remarkably
good.
ƒ Insulation Coating
A variety of surface insulations are available to choose. The smooth, tightly adherent
coating which has passed the certification of REACH and RoHs provides high
levels of insulation resistance, processability, as well as protection against high
temperature and rusting.
ƒ Good Processing Performance
The material is suitable for cut and/or punch. The users ensuring the accurate working
and correct tools are able to acquire laminations with good geometrical properties
after stamping.
ƒ Surface Condition
The surfaces shall be smooth and clean. There are no defects which will affect the
further use of the supplied materials, such as rusts, roller marks, holes, double skin,
fold marks, blisters, laminations, etc.
ƒ Characteristics of Surface Insulation Coating
Type
Oriented Electrical Steel
Non-oriented Electrical Steel
Coating Type
T2
T4
Composition
Inorganic
Semi-organic
Coating Thickness
μm
2-4
0.8-2
Interlayer Resistance
Ω.cm2/pc
≥30
≥5
Adhesion
B-F Level
A-B Level
Punching Performance
Good
Good
Rust Resistance
Good
Good
Heat Resistance
It is able to withstand 800℃ relief
annealing in non-oxidizing
atmosphere
It is able to withstand 750℃ relief
annealing in non-oxidizing
atmosphere
Corrosion Resistance
With a high corrosion resistance to insulating paint, machine oil and
refrigerating media
Remarks: Some of the new coatings are not included here and can be supplied as per users’
requirements.
ƒ Cautions for Use of Cold-rolled Electrical Steel
The punching, cutting and bending process of cold-rolled electrical steel strips
(sheets) will cause mechanical stress and strain, which will lead to the deterioration
of magnetism. The degree of deterioration increases with narrowing of the punching
width. For example, when the punching width of the core decreases from 30mm to 3
mm, the specific total loss will increase by about 40%. Therefore, the relief
annealing must be used for small motor cores, micro-motor cores and cold-rolled
oriented electrical steel strips (sheets) after being punched and bended so as to
relieve mechanical stress and strain and to restore the original magnetism of the
material.
ƒ Here is an instruction of relief annealing
1. Annealing Temperature:
The annealing temperature should not be too high and is limited to the temperature that will be
able to restore the original level of magnetism. High temperature annealing, of course, can further
improve the magnetism, but will also affect the insulation coating and cause lamination bonding.
Oriented electrical steel strips (sheets) generally applies to 800 ± 10 ℃, while non-oriented
electrical steel strips (sheets) applies to 700 ～ 750 ℃.
2. Annealing Time:
The annealing time is the holding time after the furnace temperature achieves the set temperature.
Generally it is the time required for the core to heat evenly through. The actual annealing time
depends on the way of annealing, the furnace type, the batch, the charging way and the core size. In
order to prevent the deformation of lamination due to thermal stress during heating and cooling
process, the heating rate and cooling rate must be properly controlled. The best way of heating is to
heat from the laminated side. The cooling rate depends on the batch. The cooling rate should be
lower than 30 ℃ / hour for the batch within a few tons. If the batch is larger, the cooling rate should
be lower.
3. Annealing Atmosphere
The annealing atmosphere applied should not cause oxidation and carburization of lamination,
as well as significant deterioration of insulation coating of electrical steel strips (sheets) surface.
In order not to cause oxidation of lamination, it is better to apply hydro nitrogen mixed gas with
2～10% hydrogen. The protective atmosphere dew point generally should be below 0 ℃.
4. To prevent carburization and oxidation
As the carbon content of our cold-rolled electrical steel strips (sheets) is less than 0.025%, in
order to prevent deterioration of magnetism, we must take strict precautions against carburization
during relief annealing.
The furnace materials, such as the furnace cover,
the floor should use low-carbon steel. The residual
oil on lamination surface should be cleared before
the annealing. Preventing oxidation of lamination is
an important measure to relieve stress. In addition
to the proper annealing atmosphere, it is also
important to make sure that the furnace is sealed in
good condition and nitrogen or other inert gas is
inlet for cleaning before heating.
Oriented Electrical Steel
ƒ Scope of Application
Oriented electrical steel is generally classified as conventional oriented electrical steel and
high permeability oriented electrical steel. It is widely used in transformers, large-scale
generators and other equipment cores. Compared with general oriented electrical steel, high
permeability oriented electrical steel has a higher permeability, a lower hysteresis loss,
a lower hysteresis expansion and a lower sensitivity of assembly stress.
▪ Size
Coil
Thickness
0.23mm, 0.27mm, 0.30mm
Available Width
850mm ～ 1000mm
ID
510mm
Single Weight
2 ～ 4ton
▪ Surface Insulation
Unless otherwise specified, HIB and conventional GO are supplied with inorganic
coating T2.
ƒ Magnetic Property & Stacking Factor
The properties of each grade will be lower than maximum core loss, higher than minimum
polarization and stacking factor as given in table 1. The specified value of core loss is tested
at 1.7 T and 50Hz. The specified value of magnetic polarization is tested at 800A/m.
Product
Thick
ness
mm
Steel
Grade
Theoretical
Density
kg/dm3
23RK085
Laser Scribe High
Permeability GO
0.23
23RK090
23QG090
High Permeability
Go
23QG095
7.65
7.65
27RK090
Laser Scribe High
Permeability GO
27RK095
0.27
High Permeability
Go
7.65
27RK100
27QG100
27QG120
7.65
Max. Specific
Total Loss P1.7/50
w/kg
Min. Magnetic
Polarization
B800 T
0.85
1.88
0.90
1.88
0.90
1.88
0.95
1.88
0.90
1.89
0.95
1.89
1.00
1.89
1.00
1.89
1.20
1.89
Min.
Stacking
Factor %
94.5
95.0
After stress relief heat treatment, the test specimens shall be tested as specified in GB/T 3655
ƒ Magnetic Property & Overlapping Factor Standards
Product
Thick
ness
mm
Min. Magnetic
Polarization
B800 T
1.00
1.89
1.05
1.89
1.01
1.92
1.05
1.91
23Q110
1.10
1.81
27Q120
1.20
1.82
1.30
1.81
30Q120
1.20
1.82
30Q130
1.30
1.81
30RK100
Laser Scribe High
Permeability GO
0.30
30RK105
30QG105
High Permeability
Go
Conventional GO
Theoretical
Density
kg/dm3
Max. Specific
Total Loss P1.7/50
w/kg
Steel
Grade
30QG120
0.23
0.27
0.30
27Q130
7.65
7.65
7.65
Min.
Overlapping
Factor %
95.5
94.5
95.0
95.5
Remarks: For high permeability and conventional GO, the test specimens, after stress relief heat
treatment, shall be tested as specified in GB/T 3655. For Laser Scribe high permeability GO, the test
method is GB/T 13789.
▪ Size & Tolerance
Width
mm
＞850
Thickness
mm
Thickness Tolerance
mm
0.23
±0.02
0.27
0.30
±0.03
Transverse Thickness
Tolerance mm
Width Tolerance
mm
≤0.015
＋0~
＋1.5
▪ Others
( 1) strip ( sheet ) with smooth surface, without defects such as rust, mill marks, hole, bubble,
stratification, roller printing, and so on;
( 2) the burr height is not more than 0.02mm;
( 3) flatness of the strip ( sheet ) not more than 1%, camber is not more than 1.0mm per two meters.
Non-oriented Electrical Steel
¾ Conventional Non-oriented Electrical Steel (Full Process)
Scope of Application:
The non-oriented electrical steel (full process)
is class high grade non-oriented electrical steel and mid-low
grade non-oriented electrical steel. High-grade non-oriented
electrical steel is widely used in rotating motor, small transformers
and other electromechanical equipment cores. The mid-low grade
non-oriented electrical steel is widely used in low-cost production
of household appliances and other equipments, especially
applicable to production of continuous punching machines.
▪ Size
High Grade
Thickness
Mid-low Grade
Standard
Width
Coil
Width
High Grade
Mid-low Grade
Available
Width
35WW230～35WW440
0.35mm
50WW250～50WW470
0.50mm
50WW600～50WW1300
0.50mm
35WW230～35WW440
50WW600～50WW1300
1000mm、1100mm、
1150mm、1200mm
900mm ～ 1050mm
High Grade
900mm ～ 1250mm
Mid-low Grade
510mm
Coil ID
Single Weight
1000mm
50WW250～50WW470
High Grade
2 ～ 5 ton
Mid-low Grade
2 ～ 8 ton
▪ Surface Insulation
Non-oriented electrical steel (whole process) has semi-organic insulation coating T4 (Other coatings
can be used as per users’ requirements).
▪ Size & Tolerance
Width
mm
＞1000
Thickness
mm
Thickness Tolerance
mm
Horizontal Thickness
Difference mm
Width Tolerance
mm
Camber
mm
0.35
±0.03
≤0.03
0.50
±0.03
≤0.04
+1.5
0
≤1.0
ƒ Magnetic Property & Overlapping Factor
Each steel grade is guaranteed to the max. specific total loss, the min. magnetic polarization and
the min. overlapping factor. The specific total loss is 1.5T and 50Hz. The magnetic polarization is
5000A / m.
Unless otherwise specified, each steel grade is supplied with specific total loss of 1.5T and 50Hz
and the magnetic polarization of 5000A / m.
Thickness
(mm)
0.35
0.50
Steel Grade
35WW250
35WW270
35WW300
35WW360
35WW400
35WW440
50WW250
50WW270
50WW290
50WW310
50WW350
50WW400
50WW470
50WW600
50WW700
50WW800
50WW1000
50WW1300
Theoretical
Density
(kg/dm3)
7.60
7.65
7.70
7.60
7.65
7.70
7.75
7.80
7.85
Max. Specific Total
Loss P1.5/50
(w/kg)
2.30
2.50
2.70
3.00
3.60
4.00
2.30
2.50
2.70
2.90
3.10
3.50
4.00
4.70
6.00
7.00
8.00
10.00
Min. Magnetic
Polarization B5000
(T)
1.62
1.62
1.62
1.63
1.64
1.65
1.62
1.62
1.62
1.62
1.62
1.63
1.64
1.66
1.67
1.68
1.70
1.72
Min. Overlapping
Factor (%)
95.0
97.0
▪ Typical Value of Mechanical Property & Overlapping Factor
Thickness
mm
0.35
0.50
Steel Grade
35WW250
35WW270
35WW300
35WW360
35WW400
35WW440
50WW270
50WW290
50WW310
50WW350
50WW400
50WW470
50WW600
50WW700
50WW800
50WW1000
50WW1300
Tensile Strength
Rm(MPa)
L
C
550
565
545
560
530
545
528
540
500
510
460
475
550
570
545
565
540
555
530
550
490
500
455
470
430
445
410
425
385
395
370
380
365
370
Elongation δ
(%)
L
C
19
27
20
28
22
30
27
33
32
40
38
45
22
26
25
28
28
30
30
33
36
41
38
44
43
48
45
49
46
50
48
52
50
55
Hardness
Hv5
205
200
190
180
170
160
205
202
195
190
170
152
132
122
115
109
105
Number of
Bending
L
C
12
11
13
12
17
15
28
22
35
31
35
31
12
11
13
12
14
13
16
15
19
17
28
26
35
30
40
35
41
36
43
40
44
41
Overlapping
Factor
%
97.5
98.5
Remarks: ⑴ L=Get samples parallel to rolling direction.⑵ C=Get samples perpendicular to rolling direction.
⑶ Use samples with T2 coating for overlapping factor test.⑷ All tests are performed per GB/T2522, GB/T228.
0.65mm Series of Non-oriented Electrical Steel Strips (Sheets)
▪ Scope of Application：
Mainly for large and medium-sized drive motor and micro-special motor industries. 65W530
is used for large and medium-sized torque drive motor cores, and 65W800 is used for ignitionstart motor cores.
Steel
Grade
65W530
65W800
Thickn
Specific
Magnetic
ess
Total Loss
Polarization
（mm） P15/50（w/kg） B5000（T）
0.65
Tensile
Elonga
Strength
tionδ
Rm（Mpa） （%）
Hard
ness
Hv5
Overlapping
Factor （%）
99.0
4.32
1.71
450
40
170
5.54
1.71
381
45
120
▪ International Units (SI Units) & Unit Conversion Tables
Standard Steel Grade Table of Cold-rolled Electrical Steel
Thick
ness
mm
0.27
China
Japan
Germany
US
Russia
Korea
WISCO
NSC
DIN 46400P.3
AISI(1983)
GOST21427.1
POSCO
P15/50
Steel
Grade
（w/kg）
P15/50
Steel
Grade
（w/kg）
P15/50
Steel
Grade
（w/kg）
P15/51
Steel
Grade
（w/kg）
27QG100
1.00
27ZH100
1.00
M-0H
1.03
27QG110
1.10
27ZH110
1.10
M-1H
1.09
27QG120
1.20
27Q120
1.20
27Z120
1.20
27Q130
1.30
27Z130
1.30
27Q140
1.40
VM13027S
1.30
VM-8927N
1.40
P15/51
Steel
Grade
（w/k
g）
3409
1.08
3408
1.14
P15/51
Steel
Grade
（w/kg）
27PH1
32
1.00
27PH1
45
1.10
M-3
1.21
3407
1.20
27PG1
58
1.20
M-4
1.27
3406
1.27
27PG1
72
1.30
3405
1.38
0.3
0.35
30QG100
1.00
30ZH100
1.00
30PH132
30QG105
1.05
30ZH105
1.05
30QG110
1.10
30ZH110
1.10
VM11130P
30QG120
1.20
30ZH120
1.20
VM11730P
30Q120
1.20
30Z120
30Q130
1.30
30Q140
M-0H
1.05
1.11
M-1H
1.11
3409
1.14
1.17
M-2H
1.17
3408
1.20
1.20
M-3
1.23
3407
1.26
30PG158
30Z130
1.30
M-4
1.32
3406
1.33
30PG172
1.40
30Z140
1.40
M-5
1.39
3405
1.40
30PG185
35Q135
1.35
35ZH135
1.35
M-3H
1.28
3408
1.30
35PH178
35Q145
1.45
35ZH145
1.45
M-5H
1.45
3406
1.43
35PG191
35Q155
1.55
35ZH155
1.55
VM155355
1.55
M-6H
1.57
3405
1.50
35PG204
35WW250
2.50
35H250
2.50
V25035A
2.50
36F32
0M
2.53
2413
2.50
35PN320
2.50
35WW270
2.70
35H270
2.70
V27035A
2.70
36F32
4
2.70
2412
2.70
35PN345
2.70
35WW300
3.00
35H300
3.00
V30035A
3.00
36F38
6M
3.05
2411
3.00
35PN380
3.00
35WW360
3.60
35H360
3.60
36F45
2M
3.57
35PN455
3.60
35WW400
4.00
35WW440
4.40
35H440
4.40
35PN560
4.40
VM14030S
1.40
30PH139
30PH145
0.5
50WW250
2.50
50H250
2.50
V250-50A
2.50
50WW270
2.70
50H270
2.70
V270-50A
2.70
50WW290
2.90
50H290
2.90
V290-50A
2.90
47F364M
50WW310
3.10
50H310
3.10
V310-50A
3.10
50WW350
3.50
50H350
3.50
V350-50A
50WW400
4.00
50H400
4.00
50WW470
4.70
50H470
50WW600
6.00
50WW700
50WW800
50WW1000
50WW1300
50PN320
2.50
2414
2.70
50PN350
2.70
2.87
2413
2.90
50PN370
2.90
47F397M
3.13
2412
3.10
50PN395
3.10
3.50
47F441M
3.48
2411
3.60
50PN445
3.50
V400-50A
4.00
47F529M
4.18
2312
4.00
50PN510
4.00
4.70
V470-50A
4.70
47F617M
4.88
2214
4.80
50PN595
4.70
50H600
6.00
V600-50A
6.00
2112
6.00
50PN760
6.00
7.00
50H700
7.00
V700-50A
7.00
8.00
50H800
8.00
V800-50A
10.00
50H1000
10.00
940-50SG
13.00
50H1300
13.00
100-50SG
47F882M
6.98
2012
6.50
50PN890
7.00
47F992M
8.00
2011
8.00
50PN101
5
8.00
10.00
50PN127
0
10.00
13.00
50PN165
0
13.00
8.00