Steel SPFH590-SP
Finish state
SP = skin-passed / temper-rolled coil
Light temper pass to flatten the strip, improve shape and suppress yield-point elongation (stretcher strain) on visible stampings.
Values for the SP condition
Other SPFH590 tempers and conditions
SPFH590 is listed in 4 conditions; see the grade overview at SPFH590.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SPFH590Y | Choose when deep-drawing or stretch forming dominates: lower yield point, high work hardening (n≈0.16–0.20) and higher total elongation at the same 590 MPa tensile class. | 380 | 640 | 29 | 188 HB | 8.5 % IACS |
HR-PODefault Hot rolled, pickled and oiled | Standard stocked condition for stamped automotive structural parts: clean, scale-free surface ready for forming, welding and e-coat. | 470 | 640 | 25 | 190 HB | — |
as hot rolled, mill scale (black) surface | Cheapest supply route for parts that are shot-blasted or machined after forming; scale hurts die life, paint adhesion and spot-weld consistency. | 475 | 645 | 24 | 192 HB | 8.5 % IACS |
SPThis page Skin-passed / temper-rolled coil | Light temper pass to flatten the strip, improve shape and suppress yield-point elongation (stretcher strain) on visible stampings. | 490 | 650 | 24 | 195 HB | 8.5 % IACS |
What is SPFH590-SP?
SPFH590-SP is SPFH590 supplied in the SP condition — light temper pass to flatten the strip, improve shape and suppress yield-point elongation (stretcher strain) on visible stampings. SPFH590-SP has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 650 MPa (94.3 ksi) — stronger than 61% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi). SPFH590-SP 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). HR-PO is the default condition FabDigit quotes; SP is available on request or by drawing note.
Advantages
- Readily welded — 78/100, better than 78% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
SPFH590-SP properties
Typical room-temperature values for SPFH590-SP; 22 are specific to this condition. Other listed values are SPFH590 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SPFH590-SP 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
SPFH590-SP has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 650 MPa (94.3 ksi) — stronger than 61% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
SPFH590-SP is rated for continuous service to 300°C (572 °F). It conducts heat at 46 W/m·K (26.6 BTU/hr·ft·°F), better than 71% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
SPFH590-SP conducts electricity at 8.5 % IACS, better than 63% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SPFH590-SP takes about 28 MJ of energy and emits 2.2 kg of CO₂ — less than 56% of steel grades. Typical recycled content is 20%.
Manufacturability6
SPFH590-SP's machinability is fair (47/100, worse than 58% of steel grades); weldability very good (78/100); formability good (57/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SPFH590-SP
Is SPFH590 easy to machine?
Rarely machined as a grade; drilling and trimming behave like a 190 HB medium-carbon steel — use coated carbide, rigid clamping, and expect faster punch wear than mild steel.
Can SPFH590 be welded?
Good resistance spot welding with AHSS schedules (higher force, shorter/pulsed current); MAG/laser welding fine, but HAZ softening in the martensitic phase can move failure out of the weld.
Can SPFH590 be formed, bent or molded?
Cold stampable but plan for 15–25 % springback vs mild steel, larger bend radii (≥1.5–2 t) and sheared-edge conditioning to protect hole-expansion performance; the 590Y variant is preferred for deep draws.
What surface finishes work on SPFH590?
Pickle or blast off scale, then phosphate + e-coat/paint or zinc-rich primer; bare surfaces rust quickly and the grade takes no anodizing.
SPFH590 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 |
|---|---|---|
| Ctypical mill practice; JIS G 3134 leaves C to producer within weldability limits | ≤ 0.13 | 0.08 |
| Siferrite strengthening / retained-austenite control | 0.05 – 1 | 0.4 |
| Mnhardenability for the bainite/martensite second phase | 0.8 – 2 | 1.5 |
| PJIS G 3134 limit | ≤ 0.04 | 0.02 |
| SJIS G 3134 limit; kept low for hole expansion | ≤ 0.04 | 0.01 |
| Alkilled steel | 0.02 – 0.07 | 0.04 |
| Croptional hardenability addition | ≤ 0.6 | 0.2 |
| Mooptional, some DP practices | ≤ 0.3 | 0.05 |
| Ti+Nboptional microalloying for grain refinement / hole expansion | ≤ 0.1 | 0.03 |
| Fe | balance | — |
SPFH590-SP — frequently asked
What is SPFH590-SP used for?
SPFH590-SP is typically used for chassis parts, wheels and structural brackets. In short: entry-level hot-rolled AHSS; most formable grade here; chassis stamping workhorse.
What is the yield strength of SPFH590-SP?
SPFH590-SP has a typical yield strength of 490 MPa (71.1 ksi) and a tensile strength of 650 MPa (94.3 ksi) — stronger than 61% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is SPFH590-SP easy to machine?
Reasonably — machinability is rated fair (47/100, worse than 58% of steel grades). Rarely machined as a grade; drilling and trimming behave like a 190 HB medium-carbon steel — use coated carbide, rigid clamping, and expect faster punch wear than mild steel.
Can SPFH590-SP be welded?
Yes — weldability is rated very good (78/100). Good resistance spot welding with AHSS schedules (higher force, shorter/pulsed current); MAG/laser welding fine, but HAZ softening in the martensitic phase can move failure out of the weld.
What surface finishes work on SPFH590-SP?
Pickle or blast off scale, then phosphate + e-coat/paint or zinc-rich primer; bare surfaces rust quickly and the grade takes no anodizing.
Can SPFH590-SP be formed, bent or molded?
Cold stampable but plan for 15–25 % springback vs mild steel, larger bend radii (≥1.5–2 t) and sheared-edge conditioning to protect hole-expansion performance; the 590Y variant is preferred for deep draws.
What is the maximum service temperature of SPFH590-SP?
SPFH590-SP is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between SPFH590 HR-PO and SPFH590 590Y?
HR-PO is the default condition — standard stocked condition for stamped automotive structural parts: clean, scale-free surface ready for forming, welding and e-coat. 590Y: choose when deep-drawing or stretch forming dominates: lower yield point, high work hardening (n≈0.16–0.20) and higher total elongation at the same 590 MPa tensile class. Yield strength is 470 MPa in HR-PO versus 380 MPa in 590Y.
Sources
- JIS G 3134 — Hot-rolled high strength steel sheet and strip for automobile structural uses — JSA (2018)
- Hot-rolled high-strength steel sheet for automotive use (590 MPa class) — Nippon Steel / JFE 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)
- GB/T 20564 / JAC590Y comparable dual-phase sheet specifications — SAC (2017)
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.