Steel A1011 SS Grade 50 SS50-HR
Finish state · default condition
ASTM A1011 SS Grade 50
Default service-center stock: structural-quality hot-rolled sheet/coil for brackets, frames and weldments that will be painted.
Values for the SS50-HR condition
Other A1011 SS Grade 50 tempers and conditions
A1011 SS Grade 50 is listed in 5 conditions; see the grade overview at A1011 SS Grade 50.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SS50-HRDefaultThis page SS Grade 50 | Default service-center stock: structural-quality hot-rolled sheet/coil for brackets, frames and weldments that will be painted. | 380 | 490 | 26 | 145 HB | 9 % IACS |
HSLAS Grade 50 Class 1 | Choose when 345 MPa yield is needed with maximum ductility/formability (lower minimum tensile than Class 2). | 380 | 460 | 26 | 140 HB | 9 % IACS |
HSLAS Grade 50 Class 2 | Use where a higher tensile-to-yield ratio (450 MPa min UTS) is specified, e.g. bolted structural and truck-frame parts. | 380 | 500 | 24 | 150 HB | 9 % IACS |
HSLAS-F Grade 50 | Best choice for tight roll-forming/stretch bends at 345 MPa yield: sulphide-shape-controlled, higher elongation and better bendability. | 380 | 460 | 28 | 140 HB | 9 % IACS |
SS/HSLAS Grade 50 | Order copper-bearing when mildly improved atmospheric corrosion resistance is wanted for exposed, painted or partly bare parts. | 385 | 495 | 25 | 148 HB | 8.5 % IACS |
What is A1011 SS Grade 50 SS50-HR?
A1011 SS Grade 50 SS50-HR is A1011 SS Grade 50 supplied in the SS50-HR condition — default service-center stock: structural-quality hot-rolled sheet/coil for brackets, frames and weldments that will be painted. A1011 SS Grade 50 SS50-HR has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 68% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi). A1011 SS Grade 50 SS50-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Advantages
- Readily welded — 85/100, better than 83% of steel grades
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
- Forms and bends easily — 62/100, better than 78% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
A1011 SS Grade 50 SS50-HR properties
Typical room-temperature values for A1011 SS Grade 50 SS50-HR; 22 are specific to this condition. Other listed values are A1011 SS Grade 50 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A1011 SS Grade 50 SS50-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
A1011 SS Grade 50 SS50-HR has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 68% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
A1011 SS Grade 50 SS50-HR is rated for continuous service to 350°C (662 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
A1011 SS Grade 50 SS50-HR conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of A1011 SS Grade 50 SS50-HR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
A1011 SS Grade 50 SS50-HR's machinability is good (58/100, better than 75% of steel grades); weldability excellent (85/100); formability good (62/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A1011 SS Grade 50 SS50-HR
Is A1011 SS Grade 50 easy to machine?
Machines like a C-Mn steel at ~58 % of 1212; sharp tools and rigid clamping stop thin-sheet chatter, and mill scale should be removed to protect edges.
Can A1011 SS Grade 50 be welded?
Excellent weldability by GMAW/GTAW/RSW/laser with ER70S-6 class filler; carbon equivalent is low enough that no preheat is normally needed below ~10 mm.
Can A1011 SS Grade 50 be formed, bent or molded?
Roll-forms and press-brake bends well but springback is higher than mild steel — allow larger bend radii (≈2t) and prefer HSLAS-F for tight bends.
What surface finishes work on A1011 SS Grade 50?
Not anodizable; specify pickled-and-oiled or blasted surface, then phosphate + e-coat, powder coat or hot-dip galvanize since the bare steel rusts quickly.
A1011 SS Grade 50 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 |
|---|---|---|
| CSS Gr 50 max 0.25; HSLAS Gr 50 max 0.23 | ≤ 0.25 | 0.12 |
| Mn | ≤ 1.35 | 0.85 |
| P0.04 max for HSLAS | ≤ 0.04 | 0.02 |
| Slower and shape-controlled for HSLAS-F | ≤ 0.04 | 0.01 |
| Sinot standard-limited for SS; typical mill value | ≤ 0.4 | 0.15 |
| Cuonly when copper-bearing steel is specified | ≥ 0.2 | 0.25 |
| NbHSLAS micro-alloying (Nb+V+Ti as agreed) | ≤ 0.1 | 0.03 |
| VHSLAS micro-alloying | ≤ 0.15 | 0.04 |
| TiHSLAS / HSLAS-F sulphide and grain control | ≤ 0.15 | 0.02 |
| Alkilled/deoxidized | ≤ 0.1 | 0.04 |
| Fe | balance | — |
A1011 SS Grade 50 SS50-HR — frequently asked
What is A1011 SS Grade 50 SS50-HR used for?
A1011 SS Grade 50 SS50-HR is typically used for structural stampings, automotive brackets and agricultural implements. In short: widely stocked HSLA sheet; replaces A570 and A607; low-cost 50 ksi sheet.
What is the yield strength of A1011 SS Grade 50 SS50-HR?
A1011 SS Grade 50 SS50-HR has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 68% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is A1011 SS Grade 50 SS50-HR easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like a C-Mn steel at ~58 % of 1212; sharp tools and rigid clamping stop thin-sheet chatter, and mill scale should be removed to protect edges.
Can A1011 SS Grade 50 SS50-HR be welded?
Yes — weldability is rated excellent (85/100). Excellent weldability by GMAW/GTAW/RSW/laser with ER70S-6 class filler; carbon equivalent is low enough that no preheat is normally needed below ~10 mm.
What surface finishes work on A1011 SS Grade 50 SS50-HR?
Not anodizable; specify pickled-and-oiled or blasted surface, then phosphate + e-coat, powder coat or hot-dip galvanize since the bare steel rusts quickly.
Can A1011 SS Grade 50 SS50-HR be formed, bent or molded?
Roll-forms and press-brake bends well but springback is higher than mild steel — allow larger bend radii (≈2t) and prefer HSLAS-F for tight bends.
What is the maximum service temperature of A1011 SS Grade 50 SS50-HR?
A1011 SS Grade 50 SS50-HR 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 A1011 SS Grade 50 SS50-HR and A1011 SS Grade 50 SS50-CB?
SS50-HR is the default condition — default service-center stock: structural-quality hot-rolled sheet/coil for brackets, frames and weldments that will be painted. SS50-CB: order copper-bearing when mildly improved atmospheric corrosion resistance is wanted for exposed, painted or partly bare parts. Yield strength is 380 MPa in SS50-HR versus 385 MPa in SS50-CB.
Sources
- ASTM A1011/A1011M — Standard Specification for Steel, Sheet and Strip, Hot-Rolled, Carbon, Structural, HSLA and UHSS — ASTM International (2018)
- ASTM A370 — Test Methods and Definitions for Mechanical Testing of Steel Products — ASTM International (2022)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys (HSLA sheet steels) — ASM International (1990)
- ASM Handbook Vol.19: Fatigue and Fracture — ASM International (1996)
- Hot-rolled HSLA sheet and coil product data (A1011 SS/HSLAS grades) — Cleveland-Cliffs / Nucor (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.