Steel DP450-CR (Cold rolled)
Supply condition · default condition
Standard uncoated cold-rolled continuously annealed coil/sheet; pick when the part is painted, e-coated or hot-dip coated after forming.
Values for the CR condition
Other DP450 tempers and conditions
DP450 is listed in 7 conditions; see the grade overview at DP450.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
CRDefaultThis page Cold rolled | Standard uncoated cold-rolled continuously annealed coil/sheet; pick when the part is painted, e-coated or hot-dip coated after forming. | 300 | 500 | 29 | 143 HB | 9.1 % IACS |
Electrogalvanised | Thin, very uniform electrolytic zinc on a base steel whose mechanicals stay identical to CR; used for close-tolerance visible parts. | 300 | 500 | 29 | 145 HB | 9 % IACS |
Hot-dip galvanised (GI), DP450 HCT450X+Z | Most common automotive supply form; choose for exposed or wet-side structural panels needing sacrificial zinc protection. | 310 | 500 | 28 | 146 HB | 9 % IACS |
Galvannealed | Zn-Fe alloyed coating for best paint adhesion and welding-electrode life; slightly more powdering in severe draws. | 310 | 500 | 27 | 146 HB | 9 % IACS |
Hot-dip Zn-Al-Mg coated | Zn-Al-Mg coating giving 2–5× the bare-edge and cut-edge corrosion life of GI at equal coating mass; for chassis and underbody panels. | 310 | 500 | 28 | 146 HB | 9 % IACS |
Hot rolled | Hot-rolled DP450 for thicker chassis/wheel/suspension parts where cold-rolled gauges are too thin; slightly lower elongation and rougher surface. | 330 | 490 | 26 | 148 HB | 9.1 % IACS |
2 % prestrain + paint bake | In-service condition of a formed and painted panel — quote these numbers for dent resistance and structural sizing, not the as-delivered values. | 370 | 515 | 24 | 152 HB | 9 % IACS |
What is DP450-CR?
DP450-CR is DP450 supplied in the CR condition — standard uncoated cold-rolled continuously annealed coil/sheet; pick when the part is painted, e-coated or hot-dip coated after forming. DP450-CR has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Elongation at break is 29% and the elastic modulus is 210 GPa (30.5 Msi). DP450-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,480°C (2,696 °F).
Advantages
- Ductile — tolerates forming and impact — 29%, better than 91% of steel grades
- Forms and bends easily — 75/100, better than 90% of steel grades
- Readily welded — 82/100, better than 81% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Low strength — 300 MPa (43.5 ksi), worse than 86% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
DP450-CR properties
Typical room-temperature values for DP450-CR; 18 are specific to this condition. Other listed values are DP450 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
DP450-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,480°C (2,696 °F).
Mechanical12
DP450-CR has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Elongation at break is 29% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
DP450-CR is rated for continuous service to 200°C (392 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
DP450-CR conducts electricity at 9.1 % IACS, better than 73% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of DP450-CR takes about 30 MJ of energy and emits 2.3 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 25%.
Manufacturability7
DP450-CR's machinability is good (55/100, better than 62% of steel grades); weldability very good (82/100); formability very good (75/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with DP450-CR
Is DP450 easy to machine?
Rarely machined as sheet; drilling/trimming needs sharp carbide and rigid clamping — expect higher blanking loads (~1.3× mild steel) and faster die wear.
Can DP450 be welded?
Excellent resistance spot weldability at low carbon equivalent (CEV ≈ 0.25); MIG/laser welding fine with matching or ER70S-class wire, no preheat, keep heat input moderate to limit HAZ softening of martensite.
Can DP450 be formed, bent or molded?
Deep-drawable with n≈0.18 and A80≈29 %, but allow ~2× mild-steel springback compensation, use generous die radii and clean-sheared or laser-trimmed edges to avoid stretch-flange edge cracks.
What surface finishes work on DP450?
Not anodizable; standard route is zinc coating (GI/GA/EG/ZM) or phosphate + cathodic e-coat and paint; bare CR coil must be oiled and used quickly.
DP450 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CEN 10346 HCT450X limit | ≤ 0.11 | 0.07 |
| Si | ≤ 0.5 | 0.25 |
| Mn | ≤ 1.6 | 1.2 |
| P | ≤ 0.08 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Altotal Al | 0.02 – 1 | 0.04 |
| Cr+Mohardenability addition | ≤ 1 | 0.2 |
| Nb+Timicroalloying | ≤ 0.15 | 0.03 |
| B | ≤ 0.01 | 5×10⁻⁴ |
| Fe | balance | — |
DP450-CR — frequently asked
What is DP450-CR used for?
DP450-CR is typically used for door inner panels, brackets, reinforcements and seat structures. In short: most formable dual-phase grade; best-welding DP steel; low yield ratio, bake-hardenable.
What is the yield strength of DP450-CR?
DP450-CR has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is DP450-CR easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Rarely machined as sheet; drilling/trimming needs sharp carbide and rigid clamping — expect higher blanking loads (~1.3× mild steel) and faster die wear.
Can DP450-CR be welded?
Yes — weldability is rated very good (82/100). Excellent resistance spot weldability at low carbon equivalent (CEV ≈ 0.25); MIG/laser welding fine with matching or ER70S-class wire, no preheat, keep heat input moderate to limit HAZ softening of martensite.
What surface finishes work on DP450-CR?
Not anodizable; standard route is zinc coating (GI/GA/EG/ZM) or phosphate + cathodic e-coat and paint; bare CR coil must be oiled and used quickly.
Can DP450-CR be formed, bent or molded?
Deep-drawable with n≈0.18 and A80≈29 %, but allow ~2× mild-steel springback compensation, use generous die radii and clean-sheared or laser-trimmed edges to avoid stretch-flange edge cracks.
What is the maximum service temperature of DP450-CR?
DP450-CR is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between DP450-CR and DP450-HR?
CR is the default condition — standard uncoated cold-rolled continuously annealed coil/sheet; pick when the part is painted, e-coated or hot-dip coated after forming. HR: hot-rolled DP450 for thicker chassis/wheel/suspension parts where cold-rolled gauges are too thin; slightly lower elongation and rougher surface. Yield strength is 300 MPa in CR versus 330 MPa in HR.
Sources
- EN 10346 — Continuously hot-dip coated steel flat products (HCT450X) — CEN (2015)
- VDA 239-100 — Sheet Steel for Cold Forming (CR450Y780T-class series and DP grades) — VDA (2016)
- GB/T 20564.2 — Cold rolled high strength steel sheet for automobile, Part 2: Dual phase steel — SAC (2017)
- Advanced High-Strength Steels Application Guidelines v7 — WorldAutoSteel (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Dual-phase DP450/DP500 cold-rolled and coated coil datasheets — ArcelorMittal / thyssenkrupp / Baosteel (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.