Steel SC450
JIS G5101
SC450 is the medium-strength grade of the JIS G5101 cast carbon steel series, specified at 450 MPa minimum tensile and typically supplied at 275 MPa yield, 495 MPa tensile, 24 % elongation and about 145 HB (78 HRB).
Reference datasheet — SC450 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 N condition
SC450 tempers and conditions
SC450 is supplied in 6 conditions, soft to hard. N is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Choose when maximum machinability, dimensional stability and lowest residual stress matter more than strength. | 245 | 465 | 26 | 133 HB | — |
As fabricated | Only for non-critical castings; JIS G5101 normally requires heat treatment, so as-cast is used for rough or low-duty parts. | 250 | 480 | 18 | 150 HB | 10 % IACS |
Stress relieved | Sub-critical treatment after welding or heavy machining to reduce distortion; mechanical properties stay close to the prior N/NT condition. | 270 | 485 | 25 | 140 HB | 10 % IACS |
NDefault Normalized | The standard stocked condition: refines the as-cast structure and gives the balanced 450 MPa-class strength/ductility JIS G5101 requires. | 275 | 495 | 24 | 145 HB | — |
Normalized and tempered | Pick for pressure-containing or welded castings where residual stress is relieved and impact toughness is more consistent. | 280 | 490 | 25 | 143 HB | — |
Quenched and tempered | Use when higher yield strength and better low-temperature toughness are needed from the same casting chemistry; limited by thin-section hardenability. | 410 | 590 | 21 | 12 HRC | — |
What is SC450?
SC450 is the medium-strength grade of the JIS G5101 cast carbon steel series, specified at 450 MPa minimum tensile and typically supplied at 275 MPa yield, 495 MPa tensile, 24 % elongation and about 145 HB (78 HRB). It is roughly equivalent in duty to ASTM WCB and is the default choice for general mechanical and pressure castings, with a weldability score of 78 and machinability of 62 balancing fabrication and cutting. Service is limited to about 425 °C, and the alloy has no corrosion resistance, so coating is required. Choose SC410 for easier welding or SC480 when higher strength is needed. SC450 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). SC450 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 495 MPa (71.8 ksi) — weaker than 91% of steel grades. Elongation at break is 24% and the elastic modulus is 205 GPa (29.7 Msi).
What is SC450 used for?
- pump housings
- valve bodies
- gear blanks
- structural machine parts
Advantages
- Easy to machine — 62/100, better than 89% of steel grades
- 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 — 78/100, better than 78% of steel grades
Limitations
- Low strength — 275 MPa (39.9 ksi), worse than 91% of steel grades
- Limited formability — 20/100, worse than 80% of steel grades
SC450 properties
Typical room-temperature values for SC450-N; bars are the position among steel grades.
Physical3
SC450 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
SC450 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 495 MPa (71.8 ksi) — weaker than 91% of steel grades. Elongation at break is 24% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SC450 is rated for continuous service to 425°C (797 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
SC450 conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SC450 takes about 26 MJ of energy and emits 2.1 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 80%.
Manufacturability8
SC450's machinability is good (62/100, better than 89% of steel grades); weldability very good (78/100); formability poor (20/100).
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. SC450 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with SC450
Is SC450 easy to machine?
Machines like normalized 1030–1035 steel at ~65 % of AISI 1212; watch for hard sand/scale skin and take a heavier first cut with coated carbide.
Can SC450 be welded?
Readily welded by SMAW/GMAW/FCAW with E7018-class filler; preheat 100–150 °C for sections over ~25 mm and stress relieve at 600–650 °C for pressure parts.
Can SC450 be formed, bent or molded?
Sand or shell mould casting with generous risering (steel shrinkage ~2 %); heat treat after casting to break up the coarse as-cast structure.
SC450 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 in JIS G5101; typical foundry aim for the 450 MPa class | ≤ 0.4 | 0.32 |
| SiTypical deoxidation practice, not a JIS limit | 0.2 – 0.6 | 0.4 |
| MnTypical foundry range, not a JIS limit | 0.5 – 1 | 0.75 |
| PJIS G5101 specified maximum | ≤ 0.04 | 0.02 |
| SJIS G5101 specified maximum | ≤ 0.04 | 0.02 |
| Fe | balance |
What surface finishes work on SC450?
No anodizing; shot blast then phosphate + paint, zinc-rich primer or hot-dip galvanize for outdoor service; hard chrome or nitriding possible on machined seats.
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 SC450 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- JIS
- G5101
How much does SC450 cost?
SC450 is a standard-cost steel ($$), cheaper than about 71% 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.
SC450 — frequently asked
What is SC450 used for?
SC450 is typically used for pump housings, valve bodies, gear blanks and structural machine parts. In short: JIS equivalent of WCB; balanced strength and weldability; general-purpose cast steel.
What is the yield strength of SC450?
SC450 has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 495 MPa (71.8 ksi) — weaker than 91% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is SC450 easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Machines like normalized 1030–1035 steel at ~65 % of AISI 1212; watch for hard sand/scale skin and take a heavier first cut with coated carbide.
Can SC450 be welded?
Yes — weldability is rated very good (78/100). Readily welded by SMAW/GMAW/FCAW with E7018-class filler; preheat 100–150 °C for sections over ~25 mm and stress relieve at 600–650 °C for pressure parts.
What surface finishes work on SC450?
No anodizing; shot blast then phosphate + paint, zinc-rich primer or hot-dip galvanize for outdoor service; hard chrome or nitriding possible on machined seats.
Can SC450 be formed, bent or molded?
Sand or shell mould casting with generous risering (steel shrinkage ~2 %); heat treat after casting to break up the coarse as-cast structure.
What is the maximum service temperature of SC450?
SC450 is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between SC450-N and SC450-QT?
N is the default condition — the standard stocked condition: refines the as-cast structure and gives the balanced 450 MPa-class strength/ductility JIS G5101 requires. QT: use when higher yield strength and better low-temperature toughness are needed from the same casting chemistry; limited by thin-section hardenability. Yield strength is 275 MPa in N versus 410 MPa in QT.
How much does SC450 cost?
SC450 is a standard-cost steel ($$), cheaper than about 71% 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 G5101 Carbon steel castings — Japanese Standards Association (1991)
- ASTM A216/A216M (WCB, comparable grade) — ASTM International (2018)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol. 15 — Casting — ASM International (2008)
- Machinery's Handbook (machinability ratings) — Industrial Press (2020)
- GB/T 11352 ZG270-500 (equivalent Chinese cast carbon steel) — SAC (2009)
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.