DC01 Cold Rolled Steel Coil: Material Definition
DC01 is the basic quality grade of the cold-rolled low-carbon flat steel family defined in EN 10130, carrying the material number 1.0330. The designation combines the delivery condition (D for cold rolled) with the forming class, and the grade is the modern replacement for the former St12 and FeP01 names that were withdrawn when DIN 1623 gave way to EN 10130. In everyday trade the material is often described simply as CR4 or cold reduced mild steel.
Cold-rolled coil in DC01 is produced by pickling hot-rolled strip, cold reducing it to the ordered thickness, and then annealing and skin-passing to restore ductility and a uniform surface. That sequence gives the tight thickness control, smooth finish and consistent forming behaviour that cold-rolled coil is bought for.
Standards Behind the Grade
EN 10130 - cold-rolled low-carbon flat products for cold forming, covering the required grades and mechanical properties.
EN 10131 - dimensional and shape tolerances for cold-rolled products supplied in nominal thickness.
EN 10152 - applies when the coil is electrolytically zinc coated after cold rolling.
DIN 1623 - the superseded German standard that listed the older St12, St13 and St14 grades.
Because the older and newer designation systems are still both seen on drawings, a purchase specification should always state the current standard, the grade and the surface quality class, so that a supplier can confirm that DC01 is quoted against EN 10130 and not against a withdrawn national standard.
Why 2.4 mm Thickness Is Specified
EN 10130 covers cold-rolled flat products from 0.35 mm up to below 3 mm, so a 2.4 mm coil sits inside the standard range and takes full advantage of cold-rolled properties rather than moving into hot-rolled territory. Typical reasons for selecting this gauge include:
Structural brackets and supports that need more stiffness than a 1.5 mm panel but must stay light.
Cabinets, enclosures and machine guards where a smooth, paint-ready surface matters.
Parts that are formed after cutting and cannot tolerate the scale and thickness variation of hot-rolled strip.
At this thickness the yield-to-tensile relationship and springback become more noticeable than on thin sheet, so bend radii, tool clearance and levelling practice should be set with the actual mechanical certificate to hand rather than copied from a thin-gauge job.
Coil, Sheet and Cut-to-Length Supply
| Supply form | Description | Typical use |
|---|---|---|
| Cold-rolled coil | Annealed and skin-passed, oiled or dry | Continuous feeding and high-volume forming |
| Cut-to-length sheet | Levelled from coil to fixed lengths | Laser cutting, press brake work, panels |
| Slit strip | Narrow widths cut from the master coil | Roll forming and welded tube |
Coil is normally supplied with the inside diameter, coil weight, edge condition and oiling agreed at order stage, and each coil is identified so that the heat number and mechanical properties can be traced back to the mill certificate. Surface quality is ordered as finish A or finish B depending on whether visible painted surfaces are involved.
Forming, Welding and Finishing
DC01 takes bending, coining, beading and light drawing without difficulty. Spot, seam and arc welding are all suitable, and the low carbon content keeps the heat-affected zone soft, which protects tooling and simplifies post-weld forming. After degreasing, the surface accepts paint, powder coating and zinc-rich primers readily, and adhesion is helped by the fine skin-passed surface.
Where a part needs more severe drawing than DC01 allows, DC03 or DC04 should be specified instead; these grades have lower yield strength and higher elongation, so they withstand deeper deformation without tearing. For flexible components that must not rust in service, the same cold-rolled base may be ordered with an electrolytic zinc coating to EN 10152, which keeps a smooth painted finish while adding sacrificial corrosion protection.
FAQ
Q: What does DC01 mean in steel?
It is the basic cold-rolled forming grade of EN 10130, material number 1.0330, used for simple bending, beading and light drawing work.
Q: Is DC01 the same as St12?
St12 was the earlier designation for the same grade family under DIN 1623. The current standard is EN 10130 and the current designation is DC01.
Q: Can DC01 coil be supplied at 2.4 mm?
Yes. A 2.4 mm product is within the EN 10130 range of 0.35 mm up to below 3 mm and is supplied as coil, cut-to-length sheet or slit strip.
Q: Is DC01 suitable for deep drawing?
Only for light drawing. Deep-drawn parts should use DC03 or DC04, which have lower yield strength and higher elongation than DC01.
Q: How is DC01 coil protected in transit?
Coils are oiled where agreed, wrapped and strapped on skids, with the coil number marked so the heat number and test certificate can be traced.
Q: What is the difference between EN 10130 and EN 10152?
EN 10130 covers the cold-rolled steel itself. EN 10152 applies when the same product is given an electrolytic zinc coating after rolling.