Steel SPHD HR-PO
Finish state
JIS G 3131 SPHD
Pick when scale-free surface is needed for direct stamping, welding or painting without extra descaling.
Values for the HR-PO condition
Other SPHD tempers and conditions
SPHD is listed in 3 conditions; see the grade overview at SPHD.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Cold rolled | Choose when the part needs thin gauge, tight thickness tolerance and a bright smooth surface for visible deep-drawn shells. | 200 | 300 | 40 | 92 HB | 10.8 % IACS |
HR-POThis page hot rolled, pickled and oiled | Pick when scale-free surface is needed for direct stamping, welding or painting without extra descaling. | 225 | 315 | 38 | 98 HB | 10.8 % IACS |
HRDefault Hot rolled | Default mill supply for drawn or stamped parts where the black oxide scale is acceptable or will be removed downstream. | 230 | 320 | 37 | 100 HB | 10.8 % IACS |
What is SPHD HR-PO?
SPHD HR-PO is SPHD supplied in the HR-PO condition — pick when scale-free surface is needed for direct stamping, welding or painting without extra descaling. SPHD HR-PO has a yield strength of 225 MPa (32.6 ksi) and a tensile strength of 315 MPa (45.7 ksi) — weaker than 97% of steel grades. Elongation at break is 38% and the elastic modulus is 205 GPa (29.7 Msi). SPHD HR-PO has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F). HR is the default condition FabDigit quotes; HR-PO is available on request or by drawing note.
Advantages
- Forms and bends easily — 92/100, better than 99% of steel grades
- Ductile — tolerates forming and impact — 38%, better than 98% of steel grades
- Readily welded — 93/100, better than 95% of steel grades
- High electrical conductivity — 10.8 % IACS, better than 94% of steel grades
- Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
Limitations
- Low strength — 225 MPa (32.6 ksi), worse than 97% of steel grades
SPHD HR-PO properties
Typical room-temperature values for SPHD HR-PO; 22 are specific to this condition. Other listed values are SPHD reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SPHD HR-PO has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Mechanical16
SPHD HR-PO has a yield strength of 225 MPa (32.6 ksi) and a tensile strength of 315 MPa (45.7 ksi) — weaker than 97% of steel grades. Elongation at break is 38% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SPHD HR-PO is rated for continuous service to 350°C (662 °F). It conducts heat at 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
SPHD HR-PO conducts electricity at 10.8 % IACS, better than 94% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SPHD HR-PO takes about 25 MJ of energy and emits 2.2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
SPHD HR-PO's machinability is good (56/100, better than 71% of steel grades); weldability excellent (93/100); formability excellent (92/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SPHD HR-PO
Is SPHD easy to machine?
Very soft and gummy — use sharp positive-rake tools, high speed and generous coolant to avoid burrs and built-up edge; punching and laser/plasma cutting are preferred over milling.
Can SPHD be welded?
Excellent weldability by resistance spot, MAG, TIG and laser with no preheat (CE ≈ 0.10–0.15); remove mill scale or zinc coating locally and ventilate for galvanized stock.
Can SPHD be formed, bent or molded?
Drawing-quality grade: deep-draws, stretch-flanges and roll-forms readily; watch strain-rate sensitivity, stretcher strains after long storage (age from free N) and use good drawing lubricant.
What surface finishes work on SPHD?
No corrosion resistance bare — phosphate + e-coat/powder, zinc plate or hot-dip galvanize; pickled surface accepts paint directly, black hot-rolled scale must be blasted or pickled first.
SPHD 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 |
|---|---|---|
| CJIS G 3131 SPHD ladle analysis | ≤ 0.1 | 0.06 |
| Mn | ≤ 0.5 | 0.3 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.04 | 0.01 |
| Sinot specified by JIS; mills keep low for drawability | ≤ 0.05 | 0.02 |
| Altypical Al-killed practice, not a JIS requirement | 0.02 – 0.07 | 0.04 |
| Fe | balance | — |
SPHD HR-PO — frequently asked
What is SPHD HR-PO used for?
SPHD HR-PO is typically used for drawn enclosures and housings, truck body and cab panels, pressed chassis brackets and reinforcements, appliance shells, oil pans and fluid reservoirs and HVAC duct and plenum sections. In short: deep-drawing hot-rolled sheet.
What is the yield strength of SPHD HR-PO?
SPHD HR-PO has a typical yield strength of 225 MPa (32.6 ksi) and a tensile strength of 315 MPa (45.7 ksi) — weaker than 97% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is SPHD HR-PO easy to machine?
Reasonably — machinability is rated good (56/100, better than 71% of steel grades). Very soft and gummy — use sharp positive-rake tools, high speed and generous coolant to avoid burrs and built-up edge; punching and laser/plasma cutting are preferred over milling.
Can SPHD HR-PO be welded?
Yes — weldability is rated excellent (93/100). Excellent weldability by resistance spot, MAG, TIG and laser with no preheat (CE ≈ 0.10–0.15); remove mill scale or zinc coating locally and ventilate for galvanized stock.
What surface finishes work on SPHD HR-PO?
No corrosion resistance bare — phosphate + e-coat/powder, zinc plate or hot-dip galvanize; pickled surface accepts paint directly, black hot-rolled scale must be blasted or pickled first.
Can SPHD HR-PO be formed, bent or molded?
Drawing-quality grade: deep-draws, stretch-flanges and roll-forms readily; watch strain-rate sensitivity, stretcher strains after long storage (age from free N) and use good drawing lubricant.
What is the maximum service temperature of SPHD HR-PO?
SPHD HR-PO is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between SPHD-HR and SPHD-CR?
HR is the default condition — default mill supply for drawn or stamped parts where the black oxide scale is acceptable or will be removed downstream. CR: choose when the part needs thin gauge, tight thickness tolerance and a bright smooth surface for visible deep-drawn shells. Yield strength is 230 MPa in HR versus 200 MPa in CR.
Can FabDigit make parts in SPHD HR-PO?
Yes — SPHD HR-PO is available for sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- JIS G 3131 — Hot-rolled mild steel plates, sheets and strip — Japanese Standards Association (2018)
- GB/T 912 / GB/T 3274 — Hot-rolled carbon structural and drawing steel sheet — SAC (2017)
- ASTM A1011/A1011M — Steel Sheet and Strip, Hot-Rolled, CS/DS grades — ASTM (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Machinery's Handbook, 31st ed. (machinability ratings) — Industrial Press (2020)
- Hot-rolled pickled and galvanized coil datasheets (Nippon Steel / Baosteel) — mill datasheets (2022)
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.