Steel A656 · supply condition · default condition
Steel A656-HR
Properties of the HR condition, compared with the other A656 tempers.
Standard mill condition for A656 plate — pick for welded structural weight-saving parts up to ~25 mm.
What is A656-HR?
A656-HR is A656 supplied in the HR condition — standard mill condition for A656 plate — pick for welded structural weight-saving parts up to ~25 mm. A656-HR has a yield strength of 580 MPa (84.1 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 75% of steel grades. Elongation at break is 16% and the elastic modulus is 200 GPa (29 Msi). A656-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
- Forms and bends easily — 65/100, better than 81% of steel grades
- Readily welded — 75/100, better than 76% of steel grades
- High strength — 580 MPa (84.1 ksi), better than 75% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
A656-HR properties
Typical room-temperature values for A656-HR — 11 properties are specific to this condition; the rest are grade-level values shared by every A656 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
A656-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).
Mechanical17
A656-HR has a yield strength of 580 MPa (84.1 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 75% of steel grades. Elongation at break is 16% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
A656-HR is rated for continuous service to 350°C (662 °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
A656-HR conducts electricity at 9 % IACS, better than 70% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of A656-HR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
A656-HR's machinability is fair (50/100, worse than 53% of steel grades); weldability very good (75/100); 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 A656 tempers and conditions
A656 is also supplied in 9 other conditions. The full side-by-side table is on the A656 overview.
- HRDefaultStandard mill condition for A656 plate — pick for welded structural weight-saving parts up to ~25 mm.580 MPa yield · 215 HB
- Gr100Highest A656 strength level for maximum payload / minimum plate thickness; tightest forming and welding control.720 MPa yield · 25 HRC
- CRThin-gauge cold-reduced product for stamped high-strength panels; better surface and tighter gauge, lower ductility than hot-rolled.620 MPa yield · 230 HB
- Gr80The workhorse A656 grade for dump bodies, crane booms and trailer structures.580 MPa yield · 215 HB
- GalvanizedChoose when the part is exposed outdoors and cannot be repainted; zinc coating limits service temperature and post-weld appearance.570 MPa yield · 210 HB
- Gr70Step below the popular Gr 80 when a little more bend ductility is needed.520 MPa yield · 190 HB
- Gr60Mid-level HSLA plate for lightly loaded formed structures.450 MPa yield · 160 HB
- Gr50Lowest strength level — pick when formability and weldability outrank weight saving.380 MPa yield · 140 HB
Working with A656-HR
Is A656 easy to machine?
Machines like a 200–250 HB low-alloy steel — rigid setups, coated carbide, moderate speeds; drilling and plasma/laser cutting are routine but expect edge hardening on thermally cut faces.
Can A656 be welded?
Good weldability at CE < 0.45 — use low-hydrogen (E70xx–E80xx / matching flux-cored) consumables, control heat input and preheat 100–150 °C for Gr 80/100 or thicknesses over ~20 mm.
Can A656 be formed, bent or molded?
Designed for cold bending: bend transverse to rolling direction, use generous radii (≈3–4t for Gr 80, 4–5t for Gr 100) and allow for high springback.
What surface finishes work on A656?
No inherent corrosion resistance — shot blast to SA 2.5 then zinc-rich primer/paint, hot-dip galvanize, or metallize; not anodizable.
A656 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 |
|---|---|---|
| Cheat analysis maximum | ≤ 0.18 | 0.1 |
| Mn | ≤ 1.65 | 1.4 |
| Si | ≤ 0.6 | 0.3 |
| P | ≤ 0.03 | 0.01 |
| Slower S usual for Gr 80/100 with improved formability | ≤ 0.04 | 0.01 |
| VType 3 (vanadium) chemistry | 0.05 – 0.15 | 0.08 |
| TiType 7 (titanium) chemistry | ≤ 0.1 | 0.03 |
| Nboptional microalloy addition | ≤ 0.1 | — |
| Alfine-grain practice / deoxidation | ≥ 0.02 | 0.03 |
| N | ≤ 0.02 | 0.01 |
| Fe | balance | — |
A656-HR — frequently asked
What is A656-HR used for?
A656-HR is typically used for crane booms, truck and trailer frames, dump truck bodies, hoppers and material-handling chutes, agricultural machinery structures and lifting and support beams. In short: high-strength low-alloy structural.
What is the yield strength of A656-HR?
A656-HR has a typical yield strength of 580 MPa (84.1 ksi) and a tensile strength of 660 MPa (95.7 ksi) — stronger than 75% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is A656-HR easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machines like a 200–250 HB low-alloy steel — rigid setups, coated carbide, moderate speeds; drilling and plasma/laser cutting are routine but expect edge hardening on thermally cut faces.
Can A656-HR be welded?
Yes — weldability is rated very good (75/100). Good weldability at CE < 0.45 — use low-hydrogen (E70xx–E80xx / matching flux-cored) consumables, control heat input and preheat 100–150 °C for Gr 80/100 or thicknesses over ~20 mm.
What surface finishes work on A656-HR?
No inherent corrosion resistance — shot blast to SA 2.5 then zinc-rich primer/paint, hot-dip galvanize, or metallize; not anodizable.
Can A656-HR be formed, bent or molded?
Designed for cold bending: bend transverse to rolling direction, use generous radii (≈3–4t for Gr 80, 4–5t for Gr 100) and allow for high springback.
What is the maximum service temperature of A656-HR?
A656-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 A656-HR and A656-Gr50?
HR is the default condition — standard mill condition for A656 plate — pick for welded structural weight-saving parts up to ~25 mm. Gr50: lowest strength level — pick when formability and weldability outrank weight saving. Yield strength is 580 MPa in HR versus 380 MPa in Gr50.
Can FabDigit make parts in A656-HR?
Yes — A656-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 A656/A656M — Hot-Rolled Structural Steel, HSLA Plate with Improved Formability — ASTM International (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- HSLA structural plate (A656 Gr 80) product data — Nucor / SSAB service-center literature (2023)
- GB/T 16270 (comparison grades Q550/Q690) — SAC (2009)
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.