Steel SS490
JIS SS490
SS490 is a JIS general structural steel — the higher-strength member of the SS series, strengthened by carbon and manganese rather than by alloying, and cross-referenced to ASTM A36 within the same structural family.
Reference datasheet — SS490 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the HR condition
SS490 tempers and conditions
SS490 is supplied in 7 conditions, soft to hard. HR is the default FabDigit quotes; the values on this page are for it.
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 |
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?
SS490 is a JIS general structural steel — the higher-strength member of the SS series, strengthened by carbon and manganese rather than by alloying, and cross-referenced to ASTM A36 within the same structural family. Engineers specify it when SS400 lacks strength: 320 MPa yield, 530 MPa tensile, 21 % elongation and about 155 HB (82 HRB) in the hot-rolled condition, supplied as plate, sections and bar, also normalized, annealed, cold-drawn or stress-relieved. The standard does not cap carbon, so weldability is only moderate (score 75) and heat-number carbon equivalent must be checked. Bare steel has no corrosion resistance and must be coated; use SM400A or SM490A where welded fabrication dominates. SS490 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). SS490 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 81% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi).
What is SS490 used for?
- structural steel
- machine frames
- shipbuilding
- general fabrication
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
- Readily welded — 75/100, better than 76% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Low strength — 320 MPa (46.4 ksi), worse than 81% of steel grades
SS490 properties
Typical room-temperature values for SS490-HR; bars are the position among steel grades.
Physical3
SS490 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 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 81% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SS490 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 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 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's machinability is good (58/100, better than 75% of steel grades); weldability very good (75/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. SS490 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with SS490
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.
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 |
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.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel SS490 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- A36
How much does SS490 cost?
SS490 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
SS490 — frequently asked
What is SS490 used for?
SS490 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?
SS490 has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 81% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is SS490 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% 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 be welded?
Yes — weldability is rated very good (75/100). 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?
No natural corrosion protection — shot-blast to Sa 2½ then prime/paint, hot-dip galvanize, or phosphate-and-oil; not anodizable.
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 is the maximum service temperature of SS490?
SS490 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.
How much does SS490 cost?
SS490 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
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; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.