Steel HRS HRPO
Finish state
HRPO = hot Rolled, Pickled & Oiled
Choose when you want hot-rolled price and gauge but a clean, paint- or weld-ready surface without shot blasting.
Values for the HRPO condition
Other HRS tempers and conditions
HRS is listed in 3 conditions; see the grade overview at HRS.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
HRPOThis page Hot Rolled, Pickled & Oiled | Choose when you want hot-rolled price and gauge but a clean, paint- or weld-ready surface without shot blasting. | 280 | 440 | 26 | 125 HB | — |
HRDefault Hot rolled | Cheapest structural condition — pick for weldments, frames, brackets and plate where dimensional tolerance and surface finish don't matter. | 285 | 450 | 23 | 130 HB | — |
Cold rolled | Pick for tight thickness tolerance, smooth paint-ready surface and better machined finish; costs more and has less ductility than HR. | 350 | 450 | 18 | 145 HB | — |
What is HRS HRPO?
HRS HRPO is HRS supplied in the HRPO condition — choose when you want hot-rolled price and gauge but a clean, paint- or weld-ready surface without shot blasting. HRS HRPO has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 440 MPa (63.8 ksi) — weaker than 90% of steel grades. Elongation at break is 26% and the elastic modulus is 200 GPa (29 Msi). HRS HRPO 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; HRPO is available on request or by drawing note.
Advantages
- Readily welded — 97/100, better than 100% of steel grades
- Conducts heat well — 51.9 W/m·K (30 BTU/hr·ft·°F), better than 96% of steel grades
- High electrical conductivity — 10.8 % IACS, better than 94% of steel grades
- Easy to machine — 62/100, better than 89% of steel grades
- Forms and bends easily — 72/100, better than 88% of steel grades
Limitations
- Low strength — 280 MPa (40.6 ksi), worse than 90% of steel grades
HRS HRPO properties
Typical room-temperature values for HRS HRPO; 10 are specific to this condition. Other listed values are HRS reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
HRS HRPO 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
HRS HRPO has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 440 MPa (63.8 ksi) — weaker than 90% of steel grades. Elongation at break is 26% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
HRS HRPO is rated for continuous service to 400°C (752 °F). It conducts heat at 51.9 W/m·K (30 BTU/hr·ft·°F), better than 96% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
HRS HRPO conducts electricity at 10.8 % IACS, better than 94% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of HRS HRPO takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
HRS HRPO's machinability is good (62/100, better than 89% of steel grades); weldability excellent (97/100); formability very good (72/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with HRS HRPO
Is HRS easy to machine?
Free and easy at HSS/carbide speeds but gummy — use positive rake, sharp tooling and coolant; expect a poorer finish than cold-rolled or leaded grades and remove mill scale first to protect edges.
Can HRS be welded?
Prequalified for essentially all processes (SMAW/GMAW/FCAW/RSW) with E70/ER70S-6 consumables, no preheat below ~38 mm at RT; grind off scale, oil or zinc coating before welding and ventilate zinc fume.
Can HRS be formed, bent or molded?
Bends and rolls readily cold (min bend radius ≈ 1–1.5 t hot rolled, 0.5–1 t cold rolled); hot-rolled scale can crack and mark dies, and springback is low.
What surface finishes work on HRS?
No anodizing — blast or pickle then prime; typical finishes are phosphate + powder coat/e-coat, zinc plating, hot-dip galvanizing or black oxide/oil for temporary protection.
HRS 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 |
|---|---|---|
| CA36 plate ≤0.26; A1011 CS / Q235B typically 0.12–0.20 | ≤ 0.26 | 0.18 |
| Mnwider range for thicker plate | 0.3 – 1.2 | 0.7 |
| Si0.15–0.40 when silicon-killed | ≤ 0.4 | 0.2 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.02 |
| Cu0.20 min if copper-bearing grade specified | ≤ 0.2 | 0.05 |
| Febalance, residual Cr/Ni/Mo typically <0.1 each | balance |
HRS HRPO — frequently asked
What is HRS HRPO used for?
HRS HRPO is typically used for structural plate and base plates, bracket weldments, welded machine frames and skids, sheet-metal enclosures and panels, formed channels, angles and gussets and machine guards and platform floor plate. In short: workhorse hot-rolled plate.
What is the yield strength of HRS HRPO?
HRS HRPO has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 440 MPa (63.8 ksi) — weaker than 90% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is HRS HRPO easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Free and easy at HSS/carbide speeds but gummy — use positive rake, sharp tooling and coolant; expect a poorer finish than cold-rolled or leaded grades and remove mill scale first to protect edges.
Can HRS HRPO be welded?
Yes — weldability is rated excellent (97/100). Prequalified for essentially all processes (SMAW/GMAW/FCAW/RSW) with E70/ER70S-6 consumables, no preheat below ~38 mm at RT; grind off scale, oil or zinc coating before welding and ventilate zinc fume.
What surface finishes work on HRS HRPO?
No anodizing — blast or pickle then prime; typical finishes are phosphate + powder coat/e-coat, zinc plating, hot-dip galvanizing or black oxide/oil for temporary protection.
Can HRS HRPO be formed, bent or molded?
Bends and rolls readily cold (min bend radius ≈ 1–1.5 t hot rolled, 0.5–1 t cold rolled); hot-rolled scale can crack and mark dies, and springback is low.
What is the maximum service temperature of HRS HRPO?
HRS HRPO is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between HRS-HR and HRS-CR?
HR is the default condition — cheapest structural condition — pick for weldments, frames, brackets and plate where dimensional tolerance and surface finish don't matter. CR: pick for tight thickness tolerance, smooth paint-ready surface and better machined finish; costs more and has less ductility than HR. Yield strength is 285 MPa in HR versus 350 MPa in CR.
Can FabDigit make parts in HRS HRPO?
Yes — HRS HRPO is available for CNC machining and 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
- ASTM A36/A36M Carbon Structural Steel — ASTM International (2019)
- ASTM A1011/A1011M Hot-Rolled Sheet and Strip, CS/SS/HSLAS — ASTM International (2018)
- ASTM A1008/A1008M Cold-Rolled Sheet, CS/SS/HSLAS — ASTM International (2021)
- ASTM A653/A653M Zinc-Coated (Galvanized/Galvannealed) Sheet — ASTM International (2020)
- GB/T 700 (Q235B) — SAC / (2006)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Machinery's Handbook, 31st ed. (machinability ratings) — Industrial Press (2020)
- worldsteel LCI data for steel products — World Steel Association (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.