What the DC Series Covers
The DC grades are cold rolled low carbon steel flat products for cold forming, defined in EN 10130 and still traded under the older St 12-03 style designations. They are supplied as coil, sheet, plate and strip and are chosen for the combination of extra-low carbon content, consistent mechanical properties and a surface that accepts galvanizing, lacquering and painting after normal pre-treatment.
One relationship explains the whole grade ladder: the lower the yield strength and the higher the elongation, the more severe the forming operation the sheet can survive. DC01 handles bending and simple profiles, DC03 and DC04 handle real deep drawing, and DC05 and DC06 handle the most demanding drawn parts. Low carbon also brings good weldability and machinability, so the same sheet can be arc welded, gas shielded welded or laser cut on the fabricating line.
Mechanical Properties of DC01 to DC06
| Grade | Yield strength max (MPa) | Tensile strength (MPa) | Elongation min (%) | Forming duty | Older designation |
|---|---|---|---|---|---|
| DC01 | 280 | 270-410 | 28 | Simple forming, bending, embossing | St 12-03 |
| DC03 | 240 | 270-370 | 34 | Deep drawing, difficult profiles | St 13-03 |
| DC04 | 210 | 270-350 | 38 | High deformation | St 14-03 |
| DC05 | 180 | 270-330 | 40 | Higher forming requirements | St 15-03 |
| DC06 | 170 | 270-330 | 41 | Special deep drawing | not applicable |
Chemical Composition and Cleanliness
The grade range is based on extra-low carbon, aluminium-killed steel in which carbon, manganese, phosphorus and sulphur are all restricted, with the limits tightening step by step from DC01 towards DC06.
The higher formability grades may be stabilised with titanium or niobium additions so that the sheet keeps its drawing properties after a paint baking cycle.
Non-metallic inclusion content is controlled through ladle treatment and casting practice, because inclusions are the origin of the edge cracks and slivers seen after blanking and trimming.
The chemical limits, mechanical values and tolerances for a named grade are stated in the grade standard and repeated on the mill certificate, so the order should quote them directly instead of relying on the grade name alone.
Forming Behaviour and Typical Applications
DC01: simple forming such as bending, embossing, beading and light drawing; used for cabinets, brackets, general sheet metal work and enclosure panels.
DC03: suitable for deep drawing and difficult profiles; used for appliance panels, furniture parts, drums and housings.
DC04: for high deformation requirements; used for complex housings and automotive interior panels.
DC05: for higher forming requirements; used where the draw depth or the shape complexity rules out DC04.
DC06: special deep drawing quality for the highest deformation requirements inside the standard range.
DC07: where a mill offers it, an ultra-deep-drawing quality supplied to mill specification for the most severe deformation, outside the standardised DC01 to DC06 range.
Surface Finish, Dimensions and Delivery Condition
| Item | Typical range |
|---|---|
| Grade standards | EN 10130, EN 10268 for higher strength grades, ASTM A1008, JIS G3141 |
| Thickness | 0.35-3.0 mm under the standard, thin sheet from 0.20 mm and plate up to 6.0 mm by mill agreement |
| Width | 600-1500 mm typical coil width, wider up to about 2000 mm on request |
| Length | 1-12 m cut length, or cut to size |
| Delivery condition | rolled, annealed, temper rolled, oiled, or a stated combination |
| Surface finish | ordinary, drawing quality, laminated film, passivated for lines that feed a coating plant |
| Tolerances | set by the dimensional standard of the same series as the grade standard |
Equivalent Grades and Standards Worldwide
EN 10130 is the European reference for these grades, ASTM A1008 covers cold rolled carbon steel sheet in the United States and JIS G3141 covers cold reduced sheet in Japan, with commercial quality, drawing quality and deep drawing quality designations mapping onto the DC ladder. Older national designations such as St 12-03 to St 15-03 still appear on drawings and legacy specifications, and they read directly as DC01 to DC05. When a drawing quotes several systems at once, the correct approach is to order the grade whose property table matches the forming severity of the part rather than the one whose name looks familiar. For parts that also need strength, the higher yield grades of EN 10268 with microalloying additions are the usual next step.
FAQ
Q: What is the difference between DC01, DC03 and DC04?
They are the same extra-low carbon product family with progressively lower yield strength and higher minimum elongation. DC01 is for bending, DC03 for deep drawing and difficult profiles, and DC04 for high deformation.
Q: Is DC01 the same as St 12-03?
Yes. St 12-03 is the older designation for the same grade, and the sequence continues as St 13-03 to St 15-03 for DC03 to DC05. Both designations may appear on the same mill certificate.
Q: Can cold rolled DC sheet be galvanized or painted?
Yes. The sheet is routinely supplied oiled or passivated and then hot-dip coated, electro-galvanized or painted after pre-treatment. The surface class and oil film should be agreed for the coating line concerned.
Q: Which grades suit automotive and appliance panels?
Appliance skins and automotive interior panels normally use DC03 to DC05, because those grades combine a low yield strength with the elongation needed for deep drawn housings and complex shapes.
Q: What thickness range is available?
The grade standard covers roughly 0.35 mm to 3.0 mm, while mills also supply thin sheet from about 0.20 mm and heavier plate up to 6.0 mm by agreement.
Q: Why does inclusion content matter in deep drawing grades?
Inclusions do not deform with the matrix, so they initiate edge cracks and slivers during blanking and drawing. Clean steel practice is therefore part of the specification for the higher formability grades.
