Steel SS490 HR-HEAVY
Finish state
JIS SS490
Heavy hot-rolled plate/section; minimum yield falls to 255 MPa (235 MPa above 100 mm) and toughness scatter increases.
Values for the HR-HEAVY condition
Other SS490 tempers and conditions
SS490 is listed in 7 conditions; see the grade overview at SS490.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition, used before heavy cold forming or deep machining; strength drops below the SS490 spec minimum. | 260 | 460 | 30 | 135 HB | 10 % IACS |
HR-HEAVYThis page hot rolled heavy plate | Heavy hot-rolled plate/section; minimum yield falls to 255 MPa (235 MPa above 100 mm) and toughness scatter increases. | 285 | 510 | 23 | 148 HB | 10 % IACS |
HR 16–40 mm | Same as-rolled steel in 16–40 mm thickness, where the specified minimum yield drops to 275 MPa. | 305 | 520 | 22 | 152 HB | 10 % IACS |
Stress relieved | Post-weld stress relief (typ. 580–620 °C) for dimensionally stable machine frames and pressure-bearing weldments. | 305 | 515 | 24 | 148 HB | 10 % IACS |
HRDefault Hot rolled | Standard mill condition for plate, sheet, sections and flats up to 16 mm; the default stock form. | 320 | 530 | 21 | 155 HB | — |
Normalized | Choose when a uniform fine grain and better/consistent toughness are needed in thick welded structures. | 320 | 520 | 25 | 150 HB | 10 % IACS |
Cold drawn | Cold-drawn round/flat bar for shafts and machined parts: higher strength and hardness, better surface and size tolerance, lower ductility. | 490 | 600 | 12 | 180 HB | 10 % IACS |
What is SS490 HR-HEAVY?
SS490 HR-HEAVY is SS490 supplied in the HR-HEAVY condition — heavy hot-rolled plate/section; minimum yield falls to 255 MPa (235 MPa above 100 mm) and toughness scatter increases. SS490 HR-HEAVY has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 510 MPa (74 ksi) — weaker than 89% of steel grades. Elongation at break is 23% and the elastic modulus is 205 GPa (29.7 Msi). SS490 HR-HEAVY 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). HR is the default condition FabDigit quotes; HR-HEAVY is available on request or by drawing note.
Advantages
- Conducts heat well — 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
Limitations
- Low strength — 285 MPa (41.3 ksi), worse than 89% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
SS490 HR-HEAVY properties
Typical room-temperature values for SS490 HR-HEAVY; 22 are specific to this condition. Other listed values are SS490 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SS490 HR-HEAVY 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
SS490 HR-HEAVY has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 510 MPa (74 ksi) — weaker than 89% of steel grades. Elongation at break is 23% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SS490 HR-HEAVY is rated for continuous service to 350°C (662 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
SS490 HR-HEAVY conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of SS490 HR-HEAVY takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
SS490 HR-HEAVY's machinability is good (60/100, better than 83% of steel grades); weldability good (68/100); formability good (56/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SS490 HR-HEAVY
Is SS490 easy to machine?
Machines like 1020–1025 mild steel at ~60 % of 1212; use positive-rake carbide, generous coolant and chip breakers to avoid gummy stringy chips.
Can SS490 be welded?
Readily welded by SMAW/GMAW/SAW with E70xx-class consumables; check heat-number carbon equivalent and preheat 100–150 °C for sections above ~30 mm since C is not capped by the standard.
Can SS490 be formed, bent or molded?
Cold bends fine at 1.5–2t radius across the rolling direction; hot forming 900–1200 °C, avoid working in the 200–400 °C blue-brittle range.
What surface finishes work on SS490?
No natural corrosion protection — shot-blast to Sa 2½ then prime/paint, hot-dip galvanize, or phosphate-and-oil; not anodizable.
SS490 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 |
|---|---|---|
| Cnot specified by JIS G3101; typical mill value 0.15–0.25 % | ≈ 0.2 | 0.2 |
| Sinot specified; typical 0.10–0.40 % | ≈ 0.25 | 0.25 |
| Mnnot specified; typical 0.60–1.20 % | ≈ 0.9 | 0.9 |
| PJIS G3101 limit | ≤ 0.05 | 0.02 |
| SJIS G3101 limit | ≤ 0.05 | 0.02 |
| Fe | balance | — |
SS490 HR-HEAVY — frequently asked
What is SS490 HR-HEAVY used for?
SS490 HR-HEAVY is typically used for structural steel, machine frames, shipbuilding and general fabrication. In short: stronger than SS400; low-cost structural plate; moderate weldability only.
What is the yield strength of SS490 HR-HEAVY?
SS490 HR-HEAVY has a typical yield strength of 285 MPa (41.3 ksi) and a tensile strength of 510 MPa (74 ksi) — weaker than 89% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is SS490 HR-HEAVY easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machines like 1020–1025 mild steel at ~60 % of 1212; use positive-rake carbide, generous coolant and chip breakers to avoid gummy stringy chips.
Can SS490 HR-HEAVY be welded?
Yes — weldability is rated good (68/100). Readily welded by SMAW/GMAW/SAW with E70xx-class consumables; check heat-number carbon equivalent and preheat 100–150 °C for sections above ~30 mm since C is not capped by the standard.
What surface finishes work on SS490 HR-HEAVY?
No natural corrosion protection — shot-blast to Sa 2½ then prime/paint, hot-dip galvanize, or phosphate-and-oil; not anodizable.
Can SS490 HR-HEAVY be formed, bent or molded?
Cold bends fine at 1.5–2t radius across the rolling direction; hot forming 900–1200 °C, avoid working in the 200–400 °C blue-brittle range.
What is the maximum service temperature of SS490 HR-HEAVY?
SS490 HR-HEAVY 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 SS490-HR and SS490-CD?
HR is the default condition — standard mill condition for plate, sheet, sections and flats up to 16 mm; the default stock form. CD: cold-drawn round/flat bar for shafts and machined parts: higher strength and hardness, better surface and size tolerance, lower ductility. Yield strength is 320 MPa in HR versus 490 MPa in CD.
Sources
- JIS G3101 — Rolled steels for general structure — Japanese Standards Association (2020)
- ASTM A36/A36M — Carbon Structural Steel — ASTM International (2019)
- GB/T 1591 — High strength low alloy structural steels (Q355 comparison) — SAC (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Mysteel / SMM (2026)
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.