Steel HRS · supply condition · default condition
Steel HRS-HR
Properties of the HR condition, compared with the other HRS tempers.
Cheapest structural condition — pick for weldments, frames, brackets and plate where dimensional tolerance and surface finish don't matter.
What is HRS-HR?
HRS-HR is HRS supplied in the HR condition — cheapest structural condition — pick for weldments, frames, brackets and plate where dimensional tolerance and surface finish don't matter. HRS-HR has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 89% of steel grades. Elongation at break is 23% and the elastic modulus is 200 GPa (29 Msi). HRS-HR 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).
Advantages
- Readily welded — 95/100, better than 97% 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 — 60/100, better than 83% of steel grades
- Forms and bends easily — 65/100, better than 81% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Low strength — 285 MPa (41.3 ksi), worse than 89% of steel grades
HRS-HR properties
Typical room-temperature values for HRS-HR — 13 properties are specific to this condition; the rest are grade-level values shared by every HRS temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
HRS-HR 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-HR has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 89% of steel grades. Elongation at break is 23% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
HRS-HR 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-HR conducts electricity at 10.8 % IACS, better than 94% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of HRS-HR 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-HR's machinability is good (60/100, better than 83% of steel grades); weldability excellent (95/100); formability good (65/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other HRS tempers and conditions
HRS is also supplied in 5 other conditions. The full side-by-side table is on the HRS overview.
- HRDefaultCheapest structural condition — pick for weldments, frames, brackets and plate where dimensional tolerance and surface finish don't matter.285 MPa yield · 130 HB
- CRPick for tight thickness tolerance, smooth paint-ready surface and better machined finish; costs more and has less ductility than HR.350 MPa yield · 145 HB
- EGChoose for indoor sheet metal enclosures needing a smooth, uniformly plated surface for painting; coating is too thin for outdoor exposure.300 MPa yield
- HRPOChoose when you want hot-rolled price and gauge but a clean, paint- or weld-ready surface without shot blasting.280 MPa yield · 125 HB
- GalvanizedUse outdoors or in damp service where painting is impractical; avoid where welding fume, high temperature or a Class-A paint finish is required.250 MPa yield · 120 HB
- GAPick when a galvanized part must be painted or spot-welded — matte Zn-Fe layer paints and welds better than spangled HDG but corrodes sooner.250 MPa yield
Working with HRS-HR
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-HR — frequently asked
What is HRS-HR used for?
HRS-HR 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-HR?
HRS-HR has a typical yield strength of 285 MPa (41.3 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 89% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is HRS-HR easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% 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-HR be welded?
Yes — weldability is rated excellent (95/100). 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-HR?
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-HR 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-HR?
HRS-HR 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-HR?
Yes — HRS-HR is available for CNC machining and sheet metal with instant online pricing. 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.