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   Product Introduction   Manufacturing availability   Testing Methods   Measurement Range   Comparison of Standards   Standard Packing   Sheet Weight Table   Width-Weight Curves for Coil   Hardness Test Comparison   Comparison of Gauges   Conversion Factors  

 Product Introduction
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A cold rolled steel sheet is produced by pickling a hot coil and rolling it uniformly at an appropriated temperature to a thinner thickness. It has excellent surface configuration and superb mechanical properties for use in automobile and electronic appliance production.

 Manufacturing availability
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Quality Specifications

Classification

 KSD 3512 JIS G3141 ASTM A1008 EN10130

CQ (Commercial Quality)

 SPCC SPCC CS

DC01(Fe P01)

DQ (Drawing Quality)

 SPCD SPCD DS

DC03(Fe P03)

DDQ (Deep Drawing Quality)

 SPCE SPCE DDS

DC04(Fe P04)

DDQ-N (StabilizedDeep Drawing Quality)

 SPCEN SPCEN DDS

DC04(Fe P04)

EDDQ

     EDDS

DC05(Fe P05)

 

 Classification of Products
 
  Commercial
Sheet of this quality is for simple bending or moderate forming.  Commercial steel sheet can be bent flat upon itself in any direction at room temperature. It has a wide variety of uses, including automotive panels, electrical home appliances, drums, pipes, farm implements, office supplies, building and civil work materials, and as base metal for various coatings.
 
  Drawing
Sheet of this quality has a greater degree of ductility and is more consistent in performance than commercial steel because of higher standards in production, selection and melting of the steel. It is suitable for automotive panels, audio-visual equipment, and heating apparatuses.
 
  Deep Drawing
Sheet of this designation should be used when drawing steel will not provide a sufficient degree of ductility for fabrication of parts with stringent drawing requirements, or applications that require the sheet be free from aging. This quality is produced through special steelmaking and finishing practices. It is suitable for automotive front panels and rear fenders.
 
  Stabilized Deep Drawing
Stabilized deep drawing quality products boast the highest quality in terms of workability. It is suitable for automotive parts that require complicated treatment such as front fenders or wire. As a non-aging deep drawing sheet made with Al-killed, quality is guaranteed against extreme stretching or straining.
  Surface Finish
The surface finish of cold-rolled steel sheet is either dull or bright.
  Dull Finish
Dull finish, which is attained by attaching numerous fine grains onto the steel surface, is often called 'pear-skin finish' or 'egg-shell texture'. The grains are made by steel grit blasted roll.  The dull finish is useful in drawing because lubricant oil can be evenly spread over the entire surface, thereby reducing the possibility of friction.  The fine grains also help boost paint adherence and extend the steel life span of the steel.
 
  Bright Finish
Bright finish presents high-quality roughness that is optimal for decorative purposes. The sheet surface is rolled with fine polished rolls.
 

 Edges

Classification

Specifications

Mill Edge Edges produced by trimming hot rolled coil during the pickling process, prior to cold rolling.
Slit Edge
(Trimmed Edge)		 Edges produced by shearing or slitting during the cold rolling process.
 

 Oiling
Sheet that is processed with the final step being the application of oil to the surface; usually intended to provide protection from rusting during shipment and storage. The oil may also serve to assist in the subsequent fabrication process, but this is not usually the main purpose. Dongbu Steel delivers its steel products either oiled (heavy, general or light, dos oiling, powdering) or un-oiled.

 Testing Methods
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Testing Methods
Tensile testing is performed to determine the yield strength, tensile strength, and elongation of steel sheet.

Test Specimen
All types and sizes of test pieces for tension testing are prescribed in the Specifications of KS, JIS, and ASTM. Cold rolled steel sheet, for example, generally uses the specimen collection method indicated in KS B0801. NO.5

Results

Tension test results are used as a basis for determining the workability and formability of steel sheet.

a : Elongation
Greater elongation provides increased workability.
b :

Yield Point
A lower yield point gives better shape to the end product.

c :

Yield Ratio (yield point/tensile strength)
A lower yield ratio indicates widened differentiation between tensile strength and yield point. Greater difference translates into better workability.

d :

d. Modulus of Elasticity
The modulus of elasticity is in an inverse relationship with resistance to elastic strain. Lowered resistance indicates a better formed product.

e :

n-Value (Modulus of Work Hardening)
This measure is yielded when the stress- strain curve approximates ∂=CE". Workability is proportionate to the n-value.

f :

r-Value (Modulus of Plastic Deformation)
Surface shrinkage in the direction of thickness has an inverse relationship with the r-value and the shrinkage in the direction of width is directly proportionate to the r-value. The higher the value, the less susceptible to fracture, hence better drawability.

 

 

Bending Test
The bending test is performed to determine the ductility of steel sheet. The test specimen for cold-rolled steel sheet is designated in KS B 0801 No.3. In the test, the specimen is bent to a specified angle on a mandrel or a specified radius until fracture. The ductility of the sheet is judged by the cracks on the outside of the bent specimen. A cold-rolled sheet specimen is bent 180 degrees.

 

Hardness Test

Hardness of steel sheet is closely related to other properties like strength, wear resistance, and workability. The hardness test is an easy and effective method of identifying various properties of steel sheet. The Rockwell Hardness test is used for measuring the hardness of cold-rolled steel sheet. The test method is described as follows.

Rockwell Hardness Test
Material resistance to indentation is a qualitative indication of its strength. A steel ball or diamond is often used as an indenter. The hardness value is determined by the difference in penetration depth from the application of an initial minor load onto the indenter followed by a major load. The process is repeated twice. The penetration depth on the surface depends on the increase level in pure load, namely, the B-scale and the F-scale. The B-scale uses a 1/16 (1.588 mm) steel ball indenter and the major load is 100kg. The B-scale most accurately measures specimens with the thickness of 0.762mm (0.030 in.) or over. It is preferable to use the F-scale for specimens with a thickness under 0.762mm.

 

 Workability Test

Tensile strength of cold-rolled steel sheet can be measured in various ways. Since tensile strength is developed through a complicated production process, it is difficult to measure the strength. The two most common ways to measure strength are:

Erichsen Test
This test measures the drawability of steel sheet. As is shown in the diagram, a test specimen is punched down with a steel ball plunger until the test piece cracks. The h- value, measured when the fracture occurs, is the Erichsen value.

Conical Cup Test
This method has gained popularity in recent years. The specimen is pressed with a flat or round puncher as shown in the diagram. The test value is obtained by measuring the diameter of the cup that the specimen has been drawn into. Because the value closely corresponds to the actual performance of steel sheet fabrication, this test method is widely used by automobile makers.

  

 Measurement Range
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Note:
1. Sizes indicated in will be subjected to negotiation.
2. Coil is available with an inside diameter of 508㎜(20in.) or 610㎜(24in.)
3. Coil is available in weight ranging between 2.5 tons (5,500 lbs.) are 20 tons (44,000 lbs.)

 Comparison of Standards
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Chemical Components

Standard Specification

Applications

Chemical Component

C

Si

Mn

P

S
KS D 3512
(JIS G 3141)		 SPCC CQ ≤ 0.12 - ≤ 0.50 ≤ 0.040 ≤ 0.045
SPCD DQ ≤ 0.10 - ≤ 0.45 ≤ 0.035 ≤ 0.035
SPCE (N) DDQ (Non-Aging) ≤ 0.08 - ≤ 0.40 ≤ 0.030 ≤ 0.030
ASTM A 1008 CS CQ ≤ 0.10 - ≤ 0.60 ≤ 0.030 ≤ 0.035
DS DQ ≤ 0.08 - ≤ 0.50 ≤ 0.020 ≤ 0.030
DDS DDQ (Non-Aging) ≤ 0.06 - ≤ 0.50 ≤ 0.020 ≤ 0.025
EN 10130 DC01 (Fe P01) CQ ≤ 0.12 - ≤ 0.60 ≤ 0.045 ≤ 0.045
DC03 (Fe P03) DQ ≤ 0.10 - ≤ 0.45 ≤ 0.035 ≤ 0.035
DC04 (Fe P04) DDQ (Non-Aging) ≤ 0.08 - ≤ 0.40 ≤ 0.030 ≤ 0.030
DC05 (Fe P05) EDDQ ≤ 0.06 - ≤ 0.35 ≤ 0.025 ≤ 0.025

 

 

 Mechanical Properties

Standard Specification

Application

Mechanical Property

Y.P

T.S

Elongation Min (%)
Yielding Point (N/㎟) Tensile Strength
(N/㎟)		 0.25≤t
＜0.40		 0.40≤t
＜0.60		 0.60≤t
＜1.0		 1.0≤t
＜1.6		 1.6≤t
＜2.5		 t≥2.5
KS D 3512
(JIS G 3141)		 SPCC CQ - ≥270 (32) (34) (36) (37) (38) (39)
SPCD DQ - ≥270 34 36 38 39 40 41
SPCE (N) DDQ (Non-Aging) - ≥270 36 38 40 41 42 43
ASTM A 1008 CS CQ (140~275) - 30 (L0 =50mm)
　 DS DQ (150~240) -  36 (L0 =50mm)
　 DDS DDQ (Non-Aging) (115~200) -  38 (L0 =50mm)
　 EDDS EDDQ (105~170) -  40 (L0 =50mm)
EN 10130 DC01 (Fe P01) CQ ≤ 280 270~410 28 (L0 =80mm)
　 DC03 (Fe P03) DQ ≤ 240 270~410  34 (L0 =80mm)
　 DC04 (Fe P04) DDQ (Non-Aging) ≤ 210 270~410  38 (L0 =80mm)
　 DC05 (Fe P05) EDDQ ≤ 180 270~410  40 (L0 =80mm)
 
 

Standard Specification

Mechanical Property

Hardness

Temper

HRB

Hv
KS D 3512
(JIS G 3141)		 1/8H 50~71 95~130
1/4H 65~80 115~150
1/2H 74~89 135~185

H

 ≥85 ≥170

 Standard Packing
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Dongbu Steel’s cold-rolled sheet and coil is packed to withstand handling during transportation and long-distance shipping. Special care is taken to prevent abrasion, rusting and scratching. Our packing procedure is illustrated below. The unit weight per package is usually between 2 and 5 tons for sheet and between 4 and 20 tons for coil.

Coil Packing

Sheet Packing

 


 Sheet Weight Table
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Weight

Weight per Sheet

Classification

Thickness

Width

 3ft (914mm) 3.28ft (1,000mm) 4ft (1,219mm) 5ft (1,524mm)

Length

 6ft (1,829mm) 6,56ft (2,000mm) 8ft (2,438mm) 10ft (3,048mm)

Weight Unit

in. mm lb/ft² kg/㎡ lb kg lb kg lb kg lb kg
* 0.0079 0.20 0.3226 1.570 5.81 2.63 6.94 3.14 10.3 4.67 16.1 7.29
0.0091 0.23 0.3716 1.806 6.69 3.02 8.00 3.61 11.9 5.37 18.6 8.39
* 0.0098 0.25 0.4002 1.962 7.20 3.28 8.61 3.92 12.8 5.83 20.0 9.11
* 0.0106 0.27 0.4329 2.120 7.79 3.54 9.31 4.24 13.9 6.30 21.6 9.85
* 0.0118 0.30 0.4819 2.355 8.67 3.94 10.4 4.71 15.4 7.00 24.1 10.9
0.0130 0.33 0.5309 2.590 9.56 4.33 11.4 5.18 17.0 7.70 26.5 12.0
* 0.0138 0.35 0.5636 2.748 10.1 4.59 12.1 5.50 18.0 8.17 28.2 12.8
* 0.0157 0.40 0.6412 3.140 11.5 5.25 13.8 6.28 20.5 9.33 32.1 14.6
* 0.0177 0.45 0.7229 3.532 12.0 5.91 15.6 7.06 23.1 10.5 36.1 16.4
* 0.0197 0.50 0.8045 3.925 14.5 6.56 17.3 7.85 25.7 11.7 40.2 18.2
* 0.0217 0.55 0.8862 4.318 16.0 7.22 19.1 8.64 28.4 12.8 44.3 20.1
* 0.0236 0.60 0.9638 4.710 17.3 7.88 20.7 9.42 30.8 14.0 48.2 21.9
* 0.0276 0.70 1.127 5.495 20.3 9.19 24.2 11.0 36.1 16.3 56.4 25.5
* 0.0315 0.80 1.287 6.280 23.2 10.5 27.7 12.6 41.2 18.7 64.4 29.2
* 0.0354 0.90 1.446 7.065 26.0 11.8 31.1 14.1 46.3 21.0 72.3 32.8
* 0.0394 1.00 1.609 7.850 29.0 13.1 34.6 15.7 51.5 23.3 80.5 36.5
0.0433 1.10 1.768 8.635 31.8 14.4 38.0 17.3 56.6 25.7 88.4 40.1
* 0.0472 1.20 1.928 9.420 34.7 15.8 41.5 18.8 61.7 28.0 96.4 43.8
0.0512 1.30 2.091 10.20 37.6 17.1 45.0 20.4 66.9 30.3 105 47.4
* 0.0551 1.40 2.250 10.99 40.5 18.4 48.4 22.0 72.0 32.7 113 51.0
* 0.0591 1.50 2.414 11.78 43.5 19.7 51.9 23.6 77.2 35.0 121 54.7
* 0.0630 1.60 2.573 12.56 46.3 21.0 55.4 25.1 82.3 37.3 129 58.3
* 0.0709 1.80 2.896 14.13 52.1 23.6 62.3 28.3 92.7 42.0 145 65.6
* 0.0787 2.00 3.214 15.70 57.9 26.3 69.2 31.4 103 46.7 161 72.9
* 0.0906 2.30 3.700 18.06 66.6 30.2 79.6 36.1 118 53.7 185 83.9
* 0.1024 2.60 4.182 20.41 75.3 34.1 90.0 40.8 134 60.7 209 94.8
0.1102 2.80 4.501 21.98 81.0 36.8 96.8 44.0 144 65.3 225 102
* 0.1181 3.00 4.823 23.55 86.8 39.4 104 47.1 154 70.0 241 109
* 0.1260 3.20 5.146 25.12 92.6 42.0 111 50.2 165 74.7 257 117
Note: These sizes are applicable to Korea industrial standards.
 

 Width-Weight Curves for Coil
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 Inside Diameter is 508mm (20 in)
* Coil width is the same as that of the cold-rolled strip.
* The coil lamination factor is assumed to be 100%.

 

 Hardness Test Comparison
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Rockwell Hardness Vickers
Hardness		 Rockwell Hardness Vickers
Hardness
B Scale F Scale Superficial B Scale F Scale Superficial
HB HF H30T H15T Hv HB HF H30T H15T Hv
100 113.3 80.8 90.6 235 75 99.3 64.8 82.8 140
99.5 113.0 80.5   232 74.5 99.0 64.4   138
99 112.7 80.1 90.3 229 74 98.7 64.1 82.5 137
98.5 112.4 79.8   227 73.5 98.5 63.8   136
98 112.1 7.5 90.0 224 73 98.2 63.5 82.2 134
97.5 111.9 79.2   221 72.5 97.9 63.2    
97 111.6 78.9 89.7 218 72 97.6 62.8 81.9 132
96.5 111.3 78.5   216 71.5 97.3 62.5   131
96 111.0 78.2 89.4 214 71 97.1 62.2 81.6 129
95.5 110.7 77.9   211 70.5 96.8 61.9   128
95 110.5 77.6 89.1 209 70 96.5 61.6 81.3 127
94.5 110.2 77.3   207 69 95.9 60.9 81.0 125
94 109.9 76.9 88.8 205 68 95.4 60.3 80.7 123
93.5 109.6 76.6   202 67 94.8 59.6 80.3 120
93 109.3 76.3 88.5 200 66 94.3 59.0 80.0 119
92.5 109.1 76.0   198 65 93.7 58.4 79.7 117
92 108.8 75.7 88.1 196 64 93.2 57.7 79.4 115
91.5 108.5 75.3   194 63 92.6 57.1 79.1 113
91 108.2 75.0 87.8 192 62 92.0 56.4 78.8 111
90.5 107.9 74.7   190 61 91.5 55.8 78.5 109
90 107.7 74.4 87.5 188 60 90.9 55.2 78.2 107
89.5 107.4 74.1   186 59 90.4 54.5 77.8 106
89 107.1 73.7 87.2 184 58 89.8 53.9 77.5 104
88.5 106.8 73.4   182 57 89.2 53.2 77.2 103
88 106.6 73.1 86.9 180 56 88.7 52.6 76.9 102
87.5 106.3 72.8   178 55 88.1 51.9 76.6 100
87 106.0 72.4 86.6 176 54 87.5 51.3 76.3 99
86.5 105.7 72.1   175 53 87.0 50.7 75.9 98
86 105.4 71.8 86.3 173 52 86.5 50.0 75.7 96
85.5 105.2 71.5   171 51 85.9 49.4 75.4 95
85 104.9 71.2 86.0 170 50 85.3 48.7 75.0 94
84.5 104.6 70.8   168 49 84.8 48.1 74.7 93
84 104.3 70.5 85.6 166 48 84.2 47.5 74.4 92
83.5 104.0 70.2   164 47 83.7 46.8 74.1 91
83 103.8 69.9 85.4 163 46 83.1 46.2 73.8 90
82.5 103.5 69.6   161 45 82.5 45.5 73.5 89
82 103.2 69.2 85.0 160 44 82.0 44.9 73.2 88
81.5 102.9 68.9   158 43 81.4 44.3 72.9 87
81 102.6 68.6 84.7 156 42 80.9 43.6 72.5 86
80.5 102.4 68.3   155 41 80.3 43.0 72.2 85
80 102.1 68.0 84.4 154 40 79.3 42.3 71.9 84
79.5 101.8 67.6   152 39 79.2 41.7 71.6 83
79 101.5 67.3 84.1 150 38 78.6 41.1 71.3 82
78.5 101.2 67.0   149 37 78.1 40.4 71.0 81
78 101.0 66.7 83.7 147 36 77.5 39.8 70.7 80
77.5 100.7 66.4   146 35 77.0 39.1 70.4 80
77 100.4 66.0 83.5 145 34 76.4 38.5 70 80
76.5 100.1 65.7   144 33 75.8 37.9 69.7 78
76 99.9 65.4 83.2 142 32 75.3 37.2 69.4 78
75.5 99.6 65.1   141 31 74.7 36.6 68.1 77

 

 Comparison of Gauges
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Gauge
No. 		U.S.G. B.W.G. B.G. S.W.G. M.S.G. G.S.G.
mm in. mm in. mm in. mm in. mm in. mm in.
10 3.572 0.1406 3.40 0.134 3.175 0.1250 3.251 0.128 3.416 0.1345 3.510 0.1382
11 3.175 0.1250 3.05 0.120 2.827 0.1113 2.946 0.116 3.037 0.1196 3.132 0.1233
12 2.778 0.1094 2.77 0.109 2.517 0.0991 2.64 0.104 2.657 0.1046 2.753 0.1084
13 2.381 0.0938 2.41 0.095 2.240 0.0882 2.34 0.092 2.278 0.0897 2.372 0.0934
14 1.984 0.0781 2.11 0.083 1.994 0.0785 2.03 0.080 1.897 0.0747 1.994 0.0785
15 1.786 0.0703 1.83 0.072 1.775 0.0699 1.83 0.072 1.709 0.0673 1.803 0.0710
16 1.588 0.0625 1.65 0.065 1.588 0.0625 1.63 0.064 1.519 0.0598 1.613 0.0635
17 1.429 0.0563 1.47 0.058 1.412 0.0556 1.42 0.056 1.367 0.0538 1.461 0.0575
18 1.2700 0.0500 1.24 0.049 1.257 0.0495 1.22 0.048 1.214 0.0478 1.311 0.0516
19 1.1113 0.0438 1.07 0.042 1.118 0.0440 1.02 0.040 1.062 0.0418 1.158 0.0456
20 0.9525 0.0375 0.89 0.035 0.996 0.0392 0.91 0.036 0.912 0.0359 1.006 0.0396
21 0.8731 0.0344 0.81 0.032 0.886 0.0349 0.81 0.032 0.836 0.0329 0.930 0.0366
22 0.7938 0.0313 0.71 0.028 0.794 0.0313 0.71 0.028 0.760 0.0299 0.853 0.0336
23 0.7144 0.0281 0.64 0.025 0.707 0.0278 0.61 0.024 0.683 0.0269 0.777 0.0306
24 0.6350 0.0250 0.56 0.022 0.629 0.0248 0.56 0.022 0.607 0.0239 0.701 0.0276
25 0.5556 0.0219 0.51 0.020 0.560 0.0220 0.51 0.020 0.531 0.0209 0.627 0.0247
26 0.4763 0.0188 0.46 0.018 0.498 0.0196 0.46 0.018 0.455 0.0179 0.551 0.0217
27 0.4366 0.0172 0.41 0.016 0.443 0.0175 0.417 0.0164 0.417 0.0164 0.513 0.0202
28 0.3969 0.0156 0.36 0.014 0.397 0.0156 0.376 0.0148 0.378 0.0149 0.475 0.0187
29 0.3572 0.0141 0.33 0.013 0.353 0.0139 0.345 0.0136 0.343 0.0135 0.437 0.0172
30 0.3175 0.0125 0.30 0.012 0.312 0.0123 0.315 0.0124 0.305 0.0120 0.399 0.0157
31 0.2778 0.0109 0.25 0.011 0.279 0.0110 0.295 0.0116 0.267 0.0105 0.361 0.0142
32 0.2580 0.0102 0.23 0.009 0.249 0.0098 0.274 0.0108 0.246 0.0097 0.340 0.0134
33 0.2381 0.0094 0.20 0.008 0.221 0.0087 0.254 0.0100 0.229 0.0090 - -
34 0.2183 0.0086 0.18 0.007 0.196 0.0077 0.234 0.0092 0.208 0.0082 - -
35 0.1984 0.0078 0.13 0.005 0.175 0.0069 0.213 0.0084 0.191 0.0075 - -
Note
U.S.G = United States Standard Gauge Wrough Iron 401b/f²-in.
B.W.G = Birmingham Wire Gauge
B.G = Birmingham Gauge		 S.W.G = Standard Wire Gauge
M.S.G = Manufacturer's Standard Gauge 40321b/f²-in.
G.S.G = Galvanized Sheet Gauge
 

 Conversion Factors
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Weight

 
Classification Kilogram Ounce Pound Short Ton
(2,000 lbs)		 Long Ton
(2,240 lbs)		 Metric Ton
(1,000 kg)
kg oz lb st lt t
Kilogram (kg) 1 35.2740 2.20462 0.001102 0.0₃9842 0.001
Ounce (oz) 0.02835 1 0.06250 0.0₄3125 0.0₄2790 0.0₄2835
Pound (lb) 0.45359 16 1 0.00050 0.0₃4464 0.0₃4536
Short Ton (st) 907.185 32,000 2,000 1 0.89286 0.90719
Long Ton (lt) 1,016.05 35,840 2,240 1.12 1 1.01605
Metric Ton (t) 1,000 35,274 2,204.62 1.10231 0.98421 1
(Example 0.0₃9842 = 0.0009842)

 

 

Linear Measure

 
Classification Millimeter Centimeter Meter Inch Foot Yard Mile
kg oz lb st lt t mi
Millimeter(mm) 1 0.1 0.001 0.03937 0.0032808 0.0010936 0.06214
Centimeter(cm) 10 1 0.01 0.3937 0.032808 0.010936 0.06214
Meter(m) 1,000 100 1 39.37 3.28083 1.0936 0.06214
Inch(in.) 25.40 2.540 0.0254 1 0.0833 0.02778 0.01578
Foot(ft) 304.8 30.48 0.3048 12 1 0.3333 0.01894
Yard(yd) 914.4 91.44 0.9144 36 3 1 0.05682
Mile(mi) 1,609,347.0 160,934,.70 1,609.35 63,360 5,280 1,760 1

 


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