Steel SPFH780
SPFH780 is a higher-strength JIS hot-rolled automotive sheet grade delivering DP780-level performance for chassis and structural stampings.
Reference datasheet — SPFH780 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the P&O condition
SPFH780 tempers and conditions
SPFH780 is supplied in 4 conditions, soft to hard. P&O is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
DP type | Choose for deep/stretch formed parts needing high work hardening, high crash energy absorption and good bake hardening. | 490 | 830 | 21 | 23 HRC | 8.6 % IACS |
P&ODefault Hot rolled, pickled and oiled coil/sheet | Standard stocked condition for stamped chassis parts — scale-free surface ready for forming, welding and e-coat. | 520 | 820 | 20 | 23 HRC | 8.6 % IACS |
Hot rolled | Cheapest supply form for parts that will be shot-blasted or machined; scale must be removed before forming or coating. | 520 | 820 | 20 | 23 HRC | 8.6 % IACS |
FB/Y type | Pick when the part has punched holes or sheared flanges — much higher hole-expansion ratio than the DP type at the same 780 MPa class. | 690 | 810 | 17 | 23 HRC | 8.6 % IACS |
Supply forms, finishes and certifications
Ways SPFH780 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
HDG | Hot-dip galvanized hot-rolled 780 MPa sheet | Coating |
What is SPFH780?
SPFH780 is a higher-strength JIS hot-rolled automotive sheet grade delivering DP780-level performance for chassis and structural stampings. It provides 520 MPa yield, 820 MPa tensile and 20 % elongation at 245 HB, and is available pickled and oiled (P&O), as-hot-rolled (HR), in dual-phase (DP) and ferrite-bainite (FB) variants, and hot-dip galvanized (HDG). Formability is lower than SPFH590, with high springback and sensitivity to sheared-edge condition; bare material has no corrosion resistance and must be coated or painted. Use SPFH590 where deeper draws or easier welding are needed. SPFH780 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F). SPFH780 has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 67% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
What is SPFH780 used for?
- chassis rails
- suspension parts
- wheel discs
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Difficult to machine — 35/100, worse than 84% of steel grades
SPFH780 properties
Typical room-temperature values for SPFH780-P&O; bars are the position among steel grades.
Physical3
SPFH780 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).
Mechanical16
SPFH780 has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 67% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
SPFH780 is rated for continuous service to 200°C (392 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
SPFH780 conducts electricity at 8.6 % IACS, better than 66% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SPFH780 takes about 26 MJ of energy and emits 2.1 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 25%.
Manufacturability6
SPFH780's machinability is fair (35/100, worse than 84% of steel grades); weldability very good (70/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. SPFH780 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with SPFH780
Is SPFH780 easy to machine?
Rarely machined as sheet; when drilled or trimmed use rigid setups, coated carbide and reduced feed — work hardening at cut edges is significant.
Can SPFH780 be welded?
Resistance spot welding is the primary joint; use extended/pulsed schedules and larger electrode force, expect some HAZ softening — for arc/laser welding keep heat input low and use matching or slightly overmatched filler.
Can SPFH780 be formed, bent or molded?
Design for high springback (compensated dies, extra restrike), generous bend radii (≥2.5–3 t), and avoid sheared-edge stretching — laser or fine-blanked holes greatly improve flange cracking resistance.
SPFH780 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 |
|---|---|---|
| Ckept low for weldability | 0.06 – 0.15 | 0.1 |
| Sihigher in DP/TRIP-assisted variants | 0.1 – 1.2 | 0.4 |
| Mnhardenability for martensite/bainite | 1.2 – 2.5 | 1.9 |
| P | ≤ 0.03 | 0.02 |
| Slow S + Ca treatment for hole expansion | ≤ 0.01 | 0 |
| Alkilled steel | 0.02 – 0.07 | 0.04 |
| Timicroalloy, optional | ≤ 0.15 | 0.03 |
| Nbmicroalloy, optional | ≤ 0.1 | 0.03 |
| Croptional | ≤ 0.6 | 0.25 |
| Mooptional, suppresses pearlite | ≤ 0.4 | 0.1 |
| Boptional | ≤ 0 | 8×10⁻⁴ |
| Fe | balance |
What surface finishes work on SPFH780?
Supplied bare or Zn-coated; parts must be phosphated and e-coated/painted, or hot-dip/electro-galvanized, for any exposed automotive service.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel SPFH780 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- DP780
How much does SPFH780 cost?
SPFH780 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
SPFH780 — frequently asked
What is SPFH780 used for?
SPFH780 is typically used for chassis rails, suspension parts and wheel discs. In short: hot-rolled DP780 equivalent; chassis strength upgrade; enables gauge reduction.
What is the yield strength of SPFH780?
SPFH780 has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 67% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is SPFH780 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Rarely machined as sheet; when drilled or trimmed use rigid setups, coated carbide and reduced feed — work hardening at cut edges is significant.
Can SPFH780 be welded?
Yes — weldability is rated very good (70/100). Resistance spot welding is the primary joint; use extended/pulsed schedules and larger electrode force, expect some HAZ softening — for arc/laser welding keep heat input low and use matching or slightly overmatched filler.
What surface finishes work on SPFH780?
Supplied bare or Zn-coated; parts must be phosphated and e-coated/painted, or hot-dip/electro-galvanized, for any exposed automotive service.
Can SPFH780 be formed, bent or molded?
Design for high springback (compensated dies, extra restrike), generous bend radii (≥2.5–3 t), and avoid sheared-edge stretching — laser or fine-blanked holes greatly improve flange cracking resistance.
What is the maximum service temperature of SPFH780?
SPFH780 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 SPFH780 P&O and SPFH780-FB?
P&O is the default condition — standard stocked condition for stamped chassis parts — scale-free surface ready for forming, welding and e-coat. FB: pick when the part has punched holes or sheared flanges — much higher hole-expansion ratio than the DP type at the same 780 MPa class. Yield strength is 520 MPa in P&O versus 690 MPa in FB.
How much does SPFH780 cost?
SPFH780 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- JIS G 3134 — Hot-rolled high strength steel sheet and strip for automobile structural uses — JSA (2018)
- Hot-rolled high strength steel sheets for automotive use (590–980 MPa class) — JFE Steel / Nippon Steel (2022)
- Advanced High-Strength Steels Application Guidelines v7 — WorldAutoSteel (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Steel LCI methodology report (hot rolled coil) — worldsteel (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.