Steel WC9
GB WC9 · ASTM A217 Grade WC9
WC9 is a 2.25Cr-1Mo cast steel in the ASTM A217 family — the cast counterpart to wrought P22 — supplied N+T, Q+T, annealed, or N+T plus PWHT.
Reference datasheet — WC9 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+T condition
WC9 tempers and conditions
WC9 is supplied in 4 conditions, soft to hard. N+T is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Intermediate soft condition supplied for rough machining or weld repair; must be re-normalized/tempered before code service. | 280 | 480 | 27 | 140 HB | — |
normalized, tempered and post-weld heat treated (700–760 °C) | Condition of weld-repaired or fabricated WC9 castings after the mandatory 700–760 °C PWHT; slightly softer and tougher than as-tempered. | 310 | 510 | 25 | 155 HB | 7.8 % IACS |
N+TDefault Normalized and tempered | Standard ASTM A217 delivery condition for valve bodies and pressure castings in 450–570 °C steam/hydrocarbon service. | 330 | 530 | 24 | 165 HB | — |
Quenched and tempered | Choose for heavy-section castings needing higher yield and better low-temperature toughness within the same A217 tensile band. | 400 | 575 | 22 | 185 HB | — |
What is WC9?
WC9 is a 2.25Cr-1Mo cast steel in the ASTM A217 family — the cast counterpart to wrought P22 — supplied N+T, Q+T, annealed, or N+T plus PWHT. Its creep strength suits high-temperature steam and hydrocarbon service to 570 °C, with 330 MPa yield, 530 MPa tensile, 24 % elongation and about 165 HB (85 HRB) in the default condition. Fabrication is the limiting factor: machinability rates about 50 and weldability about 45, requiring 200–300 °C preheat and 700–760 °C PWHT. It is not corrosion resistant in wet service; WC6 is the lower-temperature, easier-to-weld alternative. WC9 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). WC9 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 78% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi).
What is WC9 used for?
- High-temperature valve bodies
- Steam turbine casings
- Refinery piping fittings
Advantages
- High service temperature — 570°C (1,058 °F), better than 96% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Limited formability — 20/100, worse than 80% of steel grades
- Low strength — 330 MPa (47.9 ksi), worse than 78% of steel grades
WC9 properties
Typical room-temperature values for WC9-N+T; bars are the position among steel grades.
Physical3
WC9 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
WC9 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 78% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
WC9 is rated for continuous service to 570°C (1,058 °F). It conducts heat at 37 W/m·K (21.4 BTU/hr·ft·°F), worse than 71% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
WC9 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of WC9 takes about 31 MJ of energy and emits 2.3 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 75%.
Manufacturability8
WC9's machinability is fair (50/100, worse than 53% of steel grades); weldability fair (45/100); 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. WC9 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with WC9
Is WC9 easy to machine?
Machines like normalized 4130/4140 at roughly 55 % of 1212 — use rigid setups, carbide inserts and moderate speeds; cast skin and residual sand are abrasive, so take a heavy first cut.
Can WC9 be welded?
P-No. 5A material: preheat 200–300 °C, use E9018-B3 / ER90S-B3 (2.25Cr-1Mo) consumables, maintain interpass and apply 700–760 °C PWHT to avoid hard HAZ and reheat cracking.
Can WC9 be formed, bent or molded?
Supplied as sand or investment castings; design generous fillets and directional risering, and always normalize-and-temper the casting to break up as-cast bainitic/dendritic structure.
WC9 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 |
|---|---|---|
| C | 0.05 – 0.18 | 0.13 |
| Mn | 0.4 – 0.7 | 0.55 |
| Si | ≤ 0.6 | 0.35 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.02 |
| Cr | 2 – 2.75 | 2.35 |
| Mo | 0.9 – 1.2 | 1.05 |
| Niresidual | ≤ 0.5 | |
| Curesidual | ≤ 0.5 | |
| Wresidual | ≤ 0.1 | |
| Vresidual; total residuals ≤1.00 % | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on WC9?
Shot-blast to remove scale then aluminize, phosphate or apply high-temperature silicone/aluminium paint; not anodizable and not corrosion-resistant in wet service.
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 WC9 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A217 Grade WC9
How much does WC9 cost?
WC9 is a premium-cost steel ($$$), cheaper than about 51% 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.
WC9 — frequently asked
What is WC9 used for?
WC9 is typically used for high-temperature valve bodies, steam turbine casings and refinery piping fittings. In short: cast equivalent of P22; highest-temperature WC grade; most demanding PWHT here.
What is the yield strength of WC9?
WC9 has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 78% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is WC9 easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machines like normalized 4130/4140 at roughly 55 % of 1212 — use rigid setups, carbide inserts and moderate speeds; cast skin and residual sand are abrasive, so take a heavy first cut.
Can WC9 be welded?
With care — weldability is rated fair (45/100). P-No. 5A material: preheat 200–300 °C, use E9018-B3 / ER90S-B3 (2.25Cr-1Mo) consumables, maintain interpass and apply 700–760 °C PWHT to avoid hard HAZ and reheat cracking.
What surface finishes work on WC9?
Shot-blast to remove scale then aluminize, phosphate or apply high-temperature silicone/aluminium paint; not anodizable and not corrosion-resistant in wet service.
Can WC9 be formed, bent or molded?
Supplied as sand or investment castings; design generous fillets and directional risering, and always normalize-and-temper the casting to break up as-cast bainitic/dendritic structure.
What is the maximum service temperature of WC9?
WC9 is rated for continuous use to about 570°C (1,058 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between WC9 N+T and WC9-ANN?
N+T is the default condition — standard ASTM A217 delivery condition for valve bodies and pressure castings in 450–570 °C steam/hydrocarbon service. ANN: intermediate soft condition supplied for rough machining or weld repair; must be re-normalized/tempered before code service. Yield strength is 330 MPa in N+T versus 280 MPa in ANN.
How much does WC9 cost?
WC9 is a premium-cost steel ($$$), cheaper than about 51% 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
- ASTM A217/A217M — Steel Castings, Martensitic Stainless and Alloy, for Pressure-Containing Parts, Suitable for High-Temperature Service — ASTM International (2021)
- ASME BPVC Section II Part D — Materials, Properties — ASME (2023)
- ASME B16.34 — Valves, Flanged, Threaded and Welding End — ASME (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
- API RP 941 — Steels for Hydrogen Service at Elevated Temperatures — API (2016)
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.