What is DC07EK Enameling Steel?

If you need the highest level of deep drawing performance with superior vitreous enameling characteristics, DC07EK is the premium titanium-stabilized grade you should consider.

DC07EK is a cold-rolled low carbon steel specifically optimized for traditional enamel coating (EK suffix) with stamping level 07 (maximum deep drawing). With ultra-low carbon (≤0.008%), titanium stabilization (≤0.15%), the lowest phosphorus content (≤0.020%), and the highest plastic strain ratio (r90 ≥2.0), it delivers exceptional formability for the most demanding deep-drawn parts while ensuring superior enamel adhesion and anti-fishscale performance. Titanium addition fixes carbon and nitrogen, providing superior aging resistance.

When you use DC07EK, you benefit from the highest formability for extremely complex geometries, consistent surface quality after firing, and minimal rejects due to fish scaling, blistering, or poor adhesion. No stretcher strain marks appear during use as per GB/T 13790-2025 Table 7.

Typical applications include extra complex deep-drawn enamelware, water heater liners, high-end sanitary ware, bathtubs, automotive enamel components, and premium home appliance parts. If you need both maximum drawability and a flawless enamel finish, DC07EK gives you the highest performance titanium-stabilized foundation.

According to GB/T 13790—2025 Cold rolled low carbon steel sheet and strip for vitreous enamelling Supersedes GB/T 13790—2008 / GB/T 29515—2013
Technical Data Sheet — Grade DC07EK (Traditional Enameling Process / Maximum Deep Drawing Quality / Ti-Stabilized)
📌 Designation System Clause 4.2

DC07EK consists of four parts:

  • D — Steel flat product for cold forming
  • C — Cold rolled condition
  • 07 — Stamping level: Maximum deep drawing (Level 07)
  • EK — Enamelling type: Suitable for traditional enameling process
📖 Note: "ED" suffix indicates direct-on enameling process (also suitable for traditional), while DC07EK uses "EK" for traditional enameling with premium maximum deep drawability, titanium stabilization, and r90 ≥2.0.
📊 DC07EK vs Other Enameling Grades – Why Choose DC07EK?
1️⃣ vs DC05EK
DC05EK: C ≤0.02%, no Ti, r90 ≥1.7
DC07EK: C ≤0.008% + Ti ≤0.15%, r90 ≥2.0
Yield strength: ≤170 MPa vs ≤220 MPa (t>0.70mm)
Elongation: 40% vs 36% (t>0.70mm)
2️⃣ vs DC06EK
DC06EK: C ≤0.008% + Ti, r90 ≥1.8
DC07EK: Highest r90 (≥2.0) and elongation (≥40%)
Yield strength: ≤170 MPa vs ≤190 MPa (t>0.70mm)
Superior deep drawability for most complex parts
3️⃣ Key Advantages
  • Ultra-low carbon (≤0.008%) for maximum formability
  • Titanium stabilized (≤0.15%) for aging resistance
  • Highest plastic strain ratio r90 ≥2.0 (0.50-2.00mm)
  • Highest elongation (≥40% for t>0.70mm)
  • Lowest yield strength (≤170 MPa for t>0.70mm)
  • No stretcher strain marks during use (Table 7)
  • Hydrogen permeation validated (TH ≥6.7)
4️⃣ vs DC01EK-DC04EK
DC01EK-DC04EK: No Ti, lower r90 requirements
DC07EK: Maximum performance for extreme deep drawing
Superior aging resistance due to Ti stabilization
Strictest stretcher strain requirement
💡 Key takeaway: DC07EK delivers the highest formability among all EK-series enameling steels with ultra-low carbon (≤0.008%), titanium stabilization, and the highest plastic strain ratio (r90 ≥2.0). Choose DC07EK when your part requires the most complex maximum deep drawing geometries while maintaining superior enamel adhesion and fish-scale resistance. The r90 ≥2.0 ensures excellent deep drawability, and titanium stabilization provides superior aging resistance. No stretcher strain marks appear during use per Table 7.
🏺 Enameling Performance
🎯 Designed for
  • Traditional two-coat enameling
  • Most complex maximum deep-drawn components
  • Reduced fish-scale & blistering
✨ Key Characteristics
  • Excellent enamel adhesion (lowest P ≤0.020%)
  • Proven fish-scale resistance (TH ≥6.7)
  • Superior maximum deep drawing capability
  • Ultra-low carbon (≤0.008%) + Ti stabilization
  • Highest plastic strain ratio r90 ≥2.0
  • No stretcher strain marks during use
⚙️ What makes DC07EK the ultimate titanium-stabilized enameling steel? Its ultra-low carbon chemistry (≤0.008%) and titanium stabilization (≤0.15%) deliver maximum formability, superior aging resistance, and the cleanest surface for enamel coating. The hydrogen permeation test validates fish scale resistance (TH ≥6.7 min/mm²), while the highest elongation (up to 40%) and r90 ≥2.0 enable the most complex maximum deep-drawn shapes without cracking. Per Table 7, no stretcher strain marks appear during use.
⚙️ Chemical Composition Clause 7.1 – Table 5 (Ladle analysis)
Grade C (%) Mn (%) P (%) S (%) Als (%) Ti (%)
DC07EK ≤0.008 ≤0.50 ≤0.020 ≤0.050 ≥0.010 ≤0.15
🔬 Permissible deviations for product analysis according to GB/T 222 (Clause 7.1.2). Ultra-low carbon (≤0.008%), titanium stabilization (≤0.15%), and lowest phosphorus (≤0.020%) provide maximum formability, superior aging resistance, and excellent enamel adhesion.
📊 Mechanical Properties Clause 7.2 – Table 6
✅ Guarantee period: 6 months from manufacture date (7.2.1).
⚠️ Aging effect: yield & tensile strength may increase over time, elongation decreases – recommend early use (7.2.2). Titanium stabilization provides superior aging resistance.
Grade ReL (MPa)
≤0.50mm		 ReL (MPa)
>0.50~0.70		 ReL (MPa)
>0.70mm		 Rm (MPa) A80mm (%)
≤0.50mm		 A80mm (%)
>0.50~0.70		 A80mm (%)
>0.70mm		 r90
0.50~2.00mm		 r90
>2.00mm
DC07EK ≤210 ≤190 ≤170 270~350 ≥36 ≥38 ≥40 ≥2.0 ≥1.8
📐 When yield phenomenon not obvious, use Rp0.2. 🔧 Lower yield strength limit of 90 MPa negotiable. 🧪 P6 transverse specimen. Plastic strain ratio r90 measured at 15% plastic strain (Table 9 note). For thickness ≥1.5mm, yield strength upper limit is 225 MPa.
📏 Stretcher Strain Clause 7.3 – Table 7
Grade Stretcher strain requirements
DC01EK, DC03EK, DC04EK, DC05EK, DC03ED, DC04ED For surface quality levels FC and FD, no stretcher strains within 6 months from manufacture date.
DC07EK, DC06EK, DC06ED ✔️ No stretcher strains shall appear under room temperature storage during use. (Strictest requirement)
📌 Per Table 7, DC07EK has the strictest stretcher strain requirement: no stretcher strains shall appear during use (not just within 6 months), thanks to titanium stabilization.
📋 Enamelability Requirements Clauses 7.1.2 – 7.4.3
  • 7.1.2 – Permissible deviations for product chemical analysis shall comply with GB/T 222.
  • 7.2.1 – Mechanical properties guaranteed for 6 months from manufacture date as per Table 6.
  • 7.2.2 – Due to aging effects, properties may change over time; early use is recommended. Titanium stabilization provides superior aging resistance.
  • 7.3.1 – Skin-passing is applied, but stretcher strain tendency may reappear; titanium-stabilized grades have better resistance.
  • 7.3.2 / Table 7 – For DC07EK: no stretcher strains shall appear under room temperature storage during use.
  • 7.4.1 – Hydrogen permeation test may be carried out upon agreement to evaluate fish-scale resistance.
  • 7.4.2 – Adhesion test may be performed upon agreement; pretreatment and enameling conditions shall be stated in contract.
  • 7.4.3 – Enamelability evaluation tests are recommended for first-time use or when enamel frit/process changes.

🔬 7.4.1 Anti-fishscale (Hydrogen permeation test)

Upon agreement, hydrogen permeation test (Annex B) may be carried out. Acceptance criteria by agreement.

📍 TH = tb/d² ; Electrolyte A: TH ≥ 6.7 min/mm². Electrolyte B: TH ≥ 6.7 min/mm² (negotiable for B/Ti steels). Note: For Ti-stabilized steels like DC07EK, results and treatment need agreement between supplier and buyer per Annex B.7.2 note.

🧪 7.4.2 Enamel adhesion test

Upon agreement, adhesion test may be performed. Pretreatment and enameling conditions shall be stated in contract.

🔄 7.4.3 Enamelability evaluation test

When using material first time or enamel frit/process changes, evaluation tests are recommended.

📋 Additional Technical Requirements
Surface quality (Table 8)
FB/FC/FD available. For DC07EK: no stretcher strains during use. No cracks, blisters, folds.
Oiling & rust (7.7)
Usually oiled, 6-month rust protection. Non-oiled: supplier not liable for rust/scratches.
📌 Surface texture: Dull Ra 0.6–1.9μm; Rough Ra >1.6μm (7.6). Dimensions per GB/T 708 (7.8). Plastic strain ratio r90 ≥2.0 for thickness 0.50-2.00mm, ≥1.8 for thickness >2.00mm (Table 6).
🏭 Manufacturing & Inspection
6.2 Annealed + skin-passed | 9.2 Batch ≤30t | 8.2 Tensile 1/batch | 10 Inspection doc type 3.1
📖 International grade comparison (Annex A)
GB/T 13790—2025: DC07EK corresponds to EN 10209:2023 DC07EK. (ISO 5001:2012 does not have direct equivalent, VE05 Type 3 is for DC06EK)
🧪 Hydrogen Permeation Test Annex B
Thickness 0.50–3.00mm. TH = tb/d² ≥ 6.7 min/mm² (Electrolyte A). Note for Ti-stabilized steels: Due to lack of evidence directly relating anti-fishscale performance to hydrogen permeation time for Ti-added enameling steels, test results and treatment need agreement between supplier and buyer (Annex B.7.2 note).
✅ Why specifiers choose DC07EK enameling steel
  • Ultra-low carbon (≤0.008%) + Titanium stabilization (≤0.15%) – maximum formability, superior aging resistance, cleanest surface
  • Lowest phosphorus (≤0.020%) – best enamel adhesion among all EK series
  • Premium maximum deep drawing performance – yield strength as low as 170 MPa, elongation up to 40%
  • Highest plastic strain ratio – r90 ≥2.0 (0.50-2.00mm) / ≥1.8 (>2.00mm) for superior deep drawability
  • No stretcher strain marks during use – strictest requirement per Table 7
  • Fish scale resistance – validated by hydrogen permeation test (TH ≥6.7 min/mm²)
  • 6-month mechanical property guarantee from manufacture date
  • Hydrogen permeation / adhesion tests available upon agreement
  • Oiled option: 6-month rust protection
  • Lower yield strength limit negotiable to 90 MPa
Based on GB/T 13790—2025. Actual delivery subject to contract. Data verified per standard Tables 5, 6, 7 and Annex B. r90 values per Table 6. For Ti-stabilized DC07EK, hydrogen permeation results negotiable per Annex B.7.2 note.