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U. S. Steel Cold Rolled Sheet Steel is produced to meet a wide variety
of end-use applications. Production facilities for manufacturing cold rolled
sheet are located
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at our Gary Works (Gary, IN), Mon Valley Works (Dravosburg, PA),
Fairfield Works (Fairfield, AL), and Fairless Works (Fairless
Hills, PA) plants. Each of these plants has one or more cold
rolling mills, annealing facilities, and temper rolling mills.
Product can be purchased to either nominal decimal
thickness or minimum decimal thickness to meet a
customer’s requirement. When ordered to nominal
thickness, the product is
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manufactured to meet
the ordered thickness. Thickness tolerances vary above and
below the exact ordered thickness. For example, an order for
nominal 0.030-inch thick material is manufactured to the tolerance
range +0.0015 to - 0.0015 inch. For customer orders that
require us to meet a minimum thickness, the processing practices
are modified so that all the thickness tolerance is above the
minimum thickness ordered. The same 0.030-inch thick order is
manufactured so that the tolerance is +0.003 inch.
For tolerances related to thickness, flatness, camber, and
width, refer to the Tolerance section. These tolerances are
referred to as standard tolerances. For applications that
require more exacting dimensional tolerances, it is recommended
that customers contact U. S. Steel Sales or Technical Service personnel to
determine our capability to meet the more restrictive
tolerance(s).
Product Designations
U.S. Steel manufactures a wide variety of Cold Rolled Sheet Steel
products. They range from Commercial Steel (CS) to very highly
formable Deep Drawing Steel (DDS) to High Strength Steel (HSS).
These products are made to allow use for the manufacture of parts
requiring only simple bends, parts requiring the steel to withstand
deep draws, and parts that require a specific strength and
ductility level so they can be designed for use in load-bearing
parts.
The range of products that are available are best defined using
the designation system that is used in the ASTM specifications
related to these products. Not all products are covered by the
designators in the ASTM specifications; they will be discussed
separately.
- ASTM
Designations
The following descriptive terms are taken from the ASTM
Specification that cover Cold Rolled Steel Sheet products. The
corresponding ASTM Specification is listed for each of the
designators.
Commercial
Steel (CS) Described in ASTM Specification
A1008.
- U. S. Steel
provides CS Type B as the standard product for general
applications of cold-rolled sheet product.
Drawing Steel
(DS) Described in ASTM Specification
A1008.
- U. S. Steel
provides DS Type B as the standard product for applications
requiring drawing-steel characteristics.
Deep Drawing
Steel (DDS) Described in ASTM Specification
A1008.
- U. S. Steel
provides DDS as a low carbon steel grade to meet improved
drawability compared with DS Type B. The usual metallurgical
approach is to provide DDS as a low carbon/low manganese steel
chemistry combined with low amounts of residual elements. It is not
provided as a stabilized steel.
Extra Deep
Drawing Steel (EDDS) Described in ASTM
Specification A1008.
- U. S. Steel
provides EDDS as a vacuum degassed and chemically stabilized
grade to meet the most demanding applications for
drawability.
High Strength
Low Alloy (HSLA) Steel Described in ASTM
Specifications A606, or A1008.
- U. S. Steel
provides HSLA steel as one of two types. If manufactured using
carbon/manganese steels without microalloying with columbium,
titanium, or vanadium, the product is labeled a Structural Steel
(SS). If the product requires the use of microalloying with
columbium or vanadium to achieve high strength and improved
formability compared with SS grades, it is supplied as HSLA steel or HSLA-F
steel (Inclusion Shape Control).
Ordering Practice Terminology
Cold rolled steel sheet products can be purchased from U.S. Steel
using practices other than the ASTM specifications. Two ways are
using the SAE designator system or ordering to specific chemistry.
We have organized these products to meet the terminology of the
ASTM designators as much as possible, i.e., CS, DS, DDS, etc. The
specific grouping of all the possible types of metallurgical
designations is included in the following table. As noted, most of
the types of steel that can be ordered are grouped in one or
another designator using the ASTM product designation system. The
exceptions are products ordered to a “Specified
Hardness” or another category not yet recognized by ASTM,
Dent Resistant (Bake Hardenable) steels.
All orders, therefore, must comply with one of the following
nine product designator terms.
- Commercial Steel – CS Type B
- CS Type
B
- ASTM
A1008 CS Type B
- ASTM
A1008 CS Type B & SAE Grade 1006, 1008, 1009, 1010, or
1012
- CS Type B (Must be within the following compositional limits:
C - 0.02/0.15, Mn - 0.60 max., P - 0.030 max., S - 0.035 max.)
- Commercial Steel – CS
- ASTM
A794 CS & SAE Grade 1015 through 1023
- CS and
SAE 1015 through 1023
- Drawing Steel – DS Type B*
- DS Type
B
- ASTM
A1008 DS Type B
- DS Type B (Must be within the following compositional limits:
C - 0.02/0.08, Mn - 0.50 max., P - 0.020 max.,
and S - 0.030 max.)
- Deep Drawing Steel – DDS*
- ASTM
A1008 DDS (Composition must be within the following limits:
C - 0.06 max., Mn - 0.50 max., P - 0.020 max.,
and S - 0.025 max.)
- DDS
(Composition must be within the following limits:
C - 0.06 max., Mn - 0.50 max., P - 0.020 max., S
- 0.025 max.)
*U.S. Steel does not provide DDS as a degassed and chemically
stabilized steel.
- Extra Deep Drawing Steel – EDDS
- ASTM
A1008 EDDS (Must be vacuum degassed and chemically stabilized and
meet the following limits: C - 0.02 max., Mn - 0.40 max., P - 0.020 max., and S
- 0.020 max.)
- EDDS
(Must be vacuum degassed and chemically stabilized and meet the following
compositional limits: C - 0.02 max., Mn - 0.40 max., P - 0.020 max., and S -
0.020 max.)
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- Structural Steel**
- ASTM
A1008 Structural Steel
**Produced with carbon and manganese only. No microalloying
elements added.
- High Strength Low Alloy Steel – HSLA Steel***
- ASTM
A606, or A1008 HSLA steel or HSLA-F steel
- No ASTM
specification and ordered to meet a minimum or range in yield
strength and/or tensile strength
***Produced using microalloying technology to meet the strength and
formability requirements.
- Specified Hardness
- This
product term is not listed in the ASTM specifications. It requires
only that the cold rolled product meet a minimum hardness value or
a specified hardness range.
- Dent Resistant (Bake Hardenable)****
- BH
29
- BH
33
- BH
36
- BH
40
- BH180
- BH210
- BH240
- BH270
****These very specialized steels are manufactured to possess a
behavior in which they "age harden" after forming to
meet a higher yield strength. Usually, the product is applied for
drawn parts that are subsequently paint-cured at elevated
temperatures (up to 500°F). This allows the production
of a formable, low yield strength product during our manufacture.
Subsequent to drawing and baking (after application of the paint),
the formed part exhibits a considerably higher yield strength , and
thus, exhibits good resistance to denting. Bake Hardenable
steels are applicable for parts that require the combination of low
yield strength and high formability as produced by the steel
manufacturer, and then high resistance to denting after
fabrication. (Resistance to denting is a function of the yield
strength of the product.)
ASTM Specifications for Product Designations
- ASTM
Specification A568 This specification covers all of the
general
requirements related to Cold Rolled Steel Sheet
products. General requirements relate to
dimensional tolerances, testing practices, etc.
Items that relate to the specific product
designations are covered in the following individual
product specifications.
- ASTM
A1008
- Commercial Steel (CS)
- High
Strength with Columbium or Vanadium (HSLA or HSLA-F)
- Structural Steel (SS)
- Drawing
Steel (DS)
- Deep
Drawing Steel (DDS)
- Extra
Deep Drawing Steel (EDDS)
- ASTM
A606 High Strength Steel with Improved Corrosion Resistance
(HSLAS)
- ASTM
A794 Commercial Steel (CS) with 0.15 to 0.25%
carbon
ASTM A1008 Structural Steel Mechanical Property
Requirements
| ASTM Designation |
Yield Strength Minimum,
ksi |
Tensile Strength Minimum,
ksi |
Elongation in 2" Minimum,
% |
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Grade 25
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25
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42
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26
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Grade 30
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30
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45
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24
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Grade 33*
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33
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48
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22
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Grade 40*
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40
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52
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20
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Grade 80
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80
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82
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(a)
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(a) No requirement
* Grade 33 and Grade 40 are specified as Type 1 or Type 2
depending upon the desired chemical composition.
High Strength Sheet Steels Uniform Designator System
The uniform designator system for High Strength Sheet steel has
five basic components: (1) the sheet product prefix, (2) the
minimum yield strength in ksi, (3) a chemical composition
classification, (4) a classification for the deoxidation practice,
and (5) a classification for the minimum tensile strength.
(1) Sheet Product Prefix
HR
Hot Rolled Sheet
CR
Cold Rolled Sheet
GP
Galvanized Sheet
LT
Long Terne Coated Sheet
GL
GALVALUME® Sheet
EG
Electrogalvanized
(2)Yield Strength
Numerical
description of the minimum yield strength in ksi (3 digits are used
for
yield
strengths equal to or greater than 100 ksi).
(3) Steel Type
Each
steel type is designated by a letter classification.
S
= Structural Steel
X
= Low Alloy Steel
W
= Weathering Steel
D
= Dual Phase Steel
(4) Deoxidation Practice
–
F =
Killed Steel plus Inclusion Shape Control Practice
K =
Killed Steel Practice
(5) Tensile Strength -
Numerical
description of the minimum tensile strength in ksi (3 digits are
used for tensile
strengths equal or greater than 100 ksi).
Example of Uniform Designator System for Cold Rolled
Sheet
Product Cold Rolled
Structural Steel Sheet
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CR

Product
Prefix
(1)
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30

Yield
Strength
(2)
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X

Chemical
Composition
(3)
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K

Deoxidation
Practice
(3)
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45

Tensile
Strength
(5)
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Notes:
A). "99" in the tensile strength column indicates there
is no minimum value specified.
B). As a general rule, XK and XF designators provide products with
improved formability over SK and SF designators, respectively
C). For any given minimum yield strength, formability can be
improved by the use of special alloying additions and specialized
heat treatment, as well as by improved deoxidation practices and by
inclusion shape control.
COLD ROLLED HIGH STRENGTH SHEET
Cross References
U.
S. Steel Designator to SAE J1392
| U. S. Steel
Designator |
Trade
Names |
SAE J1392 |
| CR35SK50 |
USS HSC 35, L35 |
035AHO |
| CR37SK47 |
USS HSC 37, L37 |
----- |
| CR40SK50 |
USS HSC 40, L40 |
040AHO |
| CR40SK55 |
USS HSC 40, L40 |
040AHO |
| CR40SK50 |
USS HSC K40 |
040CLK |
| CR40XK55 |
USS EX-TEN H40 |
040YLO |
| CR40XK50 |
USS EX-TEN K40 |
040XLK |
| CR40XF50 |
USS EX-TEN F40 |
040XLF |
| CR45XF60 |
USS EX-TEN H45 |
045YHO |
| CR45XK55 |
USS EX-TEN K45 |
045XLK |
| CR45XK60 |
----- |
045YLK |
| CR45XF60 |
USS EX-TEN F45 |
045YLF |
| CR45WF65 |
USS COR-TEN A |
045WLK |
| CR45WF65 |
USS COR-TEN A-F |
045WLF |
| CR50WK60 |
----- |
050XLK |
| CR50XK60 |
USS EX-TEN K50 |
050YLF |
| CR50XF60 |
USS EX-TEN F50 |
050XLK |
| CR50XF65 |
USS EX-TEN F50 |
050YLF |
| CR80SK82 |
USS HSC 80 |
080ALO |
Note: Ordering product to a U. S. Steel High Strength Designator does
not guarantee the chemistry requirements of the cross-referenced
SAE and ASTM specifications. If an ASTM or SAE specification must
be met, the order must indicate this requirement.
Surface Finish
The surface finishes that are available on U. S. Steel Cold Rolled Sheet
are listed below. Surface finish relates to the macroscopic
roughness of the sheet surface. The designations refer to specific
surface roughness ranges as measured in arithmetic average (AA)
microinch roughness or root mean squared (RMS). The actual
roughness values can be determined quantitatively. They are
determined using a diamond-tipped tracking stylus that records the
peak heights and valley heights as the stylus is passed over the
strip surface. The most common instrument that is used to measure
the surface roughness is called a profilometer.
U.S. Steel produces Cold Rolled Sheets with the following
surface finishes:
- Regular Matte
- Light Matte
- Rough Matte
- Ground Roll Bright
- Commercial Bright
- Brushed Bright
- Embossed
These are defined with specific quantitative roughness values
that are determined using a profilometer.
- Regular Matte
This finish is widely used for most applications of cold rolled steel
sheet. The finish provides a uniform dull surface that is suitable
for painting and lacquering. The roughness as measured using a
profilometer is approximately 35 to 65 microinches.
- Light Matte
A light, matte finish is used for applications where a finish
smoother than that available with a regular matte finish is
required for improved reflectivity after painting or lacquering.
The roughness as measured by using a profilometer is approximately
20 to 45 microinches.
- Rough Matte
A rough matte finish is sometimes used for applications that
require a rougher finish than regular matte, e.g. applications
requiring porcelain enameling. The roughness as measured by using a
profilometer is approximately 55 to 90 microinches.
- Ground Roll Bright
A bright sheet surface generally used for high luster lacquered or
electroplated applications. The roughness range is approximately 20
to 40 microinches.
- Commercial Bright
Sheet that is manufactured to provide a smooth, reflective, bright
finish. The product is normally intended to be electroplated when a
highly reflective finish is required. The surface usually requires
additional buffing and polishing after plating. The product is
manufactured to meet a 10 microinches maximum roughness.
- Brushed Bright
This product has a smooth finish with a brushed appearance. Again,
it is normally used for applications where the finished part is
electroplated. The product is typically manufactured to meet 15
microinches maximum roughness.
- Embossed Steel Sheet
This is a special surface finish that is provided for applications
where a distinctive pattern is desired after painting. During
manufacture, one surface is rolled using
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a rough, patterned
roll to provide a "stamped" pattern on the surface that
is intended to be exposed after processing by the customer. The
pattern depth is typically 0.0025 to 0.0035 inch deep. U.S. Steel
provides Embossed Steel Sheet with three different types of
patterns. The patterns give a distinctive appearance to the end
product. Also, the patterns provide a "fingerprint" resistant surface,
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meaning that
fingerprints are not very noticeable when the product is touched.
The most widely used pattern is Super Seville 101.
Surface Treatments
Rust Preventative Oils
The application of surface treatments to cold rolled steel sheet is
intended to provide protection from corrosion ("rusting") during
shipment from our producing plant
and during exposure in our customers’ warehouse. Because cold
rolled steel sheet is prone to rusting, our standard practice is
to apply a rust-preventative oil at the exit end of the temper
mill (the last processing step). Rust-preventative oils are
different than forming lubricants in that they contain special
corrosion-inhibiting additions.
Additional protection from rusting can be achieved with the
application of oil to the edges of the coil after processing.
The products used for this additional "edge sealing" range
range from the same rust-inhibiting oil as applied to the surface
to special lubricants that are specifically formulated to serve as
edge sealants. Usually, these special edge sealants are more
difficult to clean prior to painting in thecustomer's shop, thus it is is important to test the use of special edge sealants for
cleanability prior to using widely.
Prelubricants
Another type of surface treatment that can be applied to cold rolled steel sheet product is called a prelubricant. The
function of a prelubricant is to allow the steel to be deeply drawn in a
customer's operation without the need to apply special
drawing compounds in the customer's plant. The purchase of a
prelubricated sheet generally allows the customer to avoid the
often messy application of a drawing compound; thereby,
allowing him to maintain a cleaner manufacturing plant.
Prelubricants are typically used only for applications that require
a deep drawing operation. They are more costly than
rust-preventative oils, and they are generally more difficult to
remove prior to painting. As a result, paint adhesion may be
worsened and paint blistering might occur if the prelubricant is
not properly removed.
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