Steel DP780 · supply condition · default condition
Steel DP780-CR
Properties of the CR condition, compared with the other DP780 tempers.
Standard uncoated cold-rolled DP780 sheet for painted/e-coated interior structural stampings.
What is DP780-CR?
DP780-CR is DP780 supplied in the CR condition — standard uncoated cold-rolled DP780 sheet for painted/e-coated interior structural stampings. DP780-CR has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 63% of steel grades. Elongation at break is 16% and the elastic modulus is 207 GPa (30 Msi). DP780-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F).
Limitations
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
DP780-CR properties
Typical room-temperature values for DP780-CR — 10 properties are specific to this condition; the rest are grade-level values shared by every DP780 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
DP780-CR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F).
Mechanical14
DP780-CR has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 63% of steel grades. Elongation at break is 16% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
DP780-CR is rated for continuous service to 250°C (482 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 64% of steel grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
DP780-CR conducts electricity at 8.6 % IACS, better than 66% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of DP780-CR takes about 30 MJ of energy and emits 2.3 kg of CO₂ — more than 55% of steel grades. Typical recycled content is 25%.
Manufacturability6
DP780-CR's machinability is fair (42/100, worse than 72% of steel grades); weldability very good (72/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other DP780 tempers and conditions
DP780 is also supplied in 4 other conditions. The full side-by-side table is on the DP780 overview.
- CRDefaultStandard uncoated cold-rolled DP780 sheet for painted/e-coated interior structural stampings.500 MPa yield · 245 HB
- GalvanizedChoose for corrosion-exposed body-in-white parts needing cathodic zinc protection; slightly lower strength scatter from the galvanizing thermal cycle.495 MPa yield · 250 HV
Working with DP780-CR
Is DP780 easy to machine?
Rarely machined; drilling/trimming needs sharp carbide or laser cutting — trimmed edges are notch-sensitive and should be deburred to avoid edge cracking.
Can DP780 be welded?
Good resistance spot weldability with reduced current and longer hold/post-pulse to limit HAZ softening and interfacial fracture; laser and MAG welding fine, avoid heavy heat input that tempers the martensite.
Can DP780 be formed, bent or molded?
High n-value gives good stretch forming but expect 2–3× the springback of mild steel — compensate dies, use over-crown/post-stretch, and keep generous bend radii (≥3–4 t) with burr-free blanks.
What surface finishes work on DP780?
Zinc coating (GI/GA/EG) plus phosphate and e-coat is the standard protection route; bare CR must be oiled in storage and painted in service, no anodizing applies.
DP780 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 |
|---|---|---|
| Ccontrols martensite hardness | 0.08 – 0.18 | 0.13 |
| Mnhardenability | 1.2 – 2.5 | 1.9 |
| Si | 0.1 – 0.8 | 0.35 |
| CrCr+Mo typically ≤1.0 combined | 0 – 0.8 | 0.25 |
| Mosuppresses pearlite on cooling | 0 – 0.4 | 0.15 |
| Aldeoxidation | 0.02 – 0.1 | 0.04 |
| Nbgrain refinement (optional) | 0 – 0.1 | 0.02 |
| Tioptional microalloy | 0 – 0.15 | 0.02 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Boptional | 0 – 0.01 | 0 |
| Fe | balance | — |
DP780-CR — frequently asked
What is DP780-CR used for?
DP780-CR is typically used for B-pillar reinforcements, bumper beams and bumper beam brackets, longitudinal frame rails, seat frames, body cross members and door impact beams. In short: workhorse dual-phase sheet.
What is the yield strength of DP780-CR?
DP780-CR has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 63% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is DP780-CR easy to machine?
Not especially — machinability is rated fair (42/100, worse than 72% of steel grades). Rarely machined; drilling/trimming needs sharp carbide or laser cutting — trimmed edges are notch-sensitive and should be deburred to avoid edge cracking.
Can DP780-CR be welded?
Yes — weldability is rated very good (72/100). Good resistance spot weldability with reduced current and longer hold/post-pulse to limit HAZ softening and interfacial fracture; laser and MAG welding fine, avoid heavy heat input that tempers the martensite.
What surface finishes work on DP780-CR?
Zinc coating (GI/GA/EG) plus phosphate and e-coat is the standard protection route; bare CR must be oiled in storage and painted in service, no anodizing applies.
Can DP780-CR be formed, bent or molded?
High n-value gives good stretch forming but expect 2–3× the springback of mild steel — compensate dies, use over-crown/post-stretch, and keep generous bend radii (≥3–4 t) with burr-free blanks.
What is the maximum service temperature of DP780-CR?
DP780-CR is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between DP780-CR and DP780-HR?
CR is the default condition — standard uncoated cold-rolled DP780 sheet for painted/e-coated interior structural stampings. HR: use for chassis, control arms and wheel discs where gauge above ~2.5 mm is needed and surface finish is secondary. Yield strength is 500 MPa in CR versus 520 MPa in HR.
Can FabDigit make parts in DP780-CR?
Yes — DP780-CR is available for sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10346 — Continuously hot-dip coated steel flat products (HCT780X) — CEN (2015)
- SAE J2745 — Steel, High Strength, Dual Phase, Cold Rolled and Coated Sheet — SAE International (2018)
- GB/T 20564.2 — Cold rolled dual phase steel sheet for automobile — SAC (2017)
- Advanced High-Strength Steels Application Guidelines V7 — WorldAutoSteel (2021)
- Dual phase steel DP780 / DP800 cold rolled and coated data sheets — ArcelorMittal / Baosteel / voestalpine (2023)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
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.