Steel WC4-ANN (Annealed)
Heat-treated state
GB WC4 · ASTM A217 Grade WC4
Soft intermediate state used for rough machining or weld repair; not an A217 acceptance condition and must be re-normalized/tempered before service.
Values for the ANN condition
Other WC4 tempers and conditions
WC4 is listed in 3 conditions; see the grade overview at WC4.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNThis page Annealed | Soft intermediate state used for rough machining or weld repair; not an A217 acceptance condition and must be re-normalized/tempered before service. | 260 | 470 | 28 | 140 HB | 8.1 % IACS |
N+TDefault Normalized and tempered | Standard supply condition for A217 WC4 pressure castings of ordinary section size. | 335 | 545 | 24 | 163 HB | — |
Quenched and tempered | Choose for heavy sections or when upper-range strength and better low-temperature toughness are required. | 400 | 585 | 22 | 180 HB | — |
What is WC4-ANN?
WC4-ANN is WC4 heat treated to ANN — soft intermediate state used for rough machining or weld repair; not an A217 acceptance condition and must be re-normalized/tempered before service. WC4-ANN has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 92% of steel grades. Elongation at break is 28% and the elastic modulus is 200 GPa (29 Msi). WC4-ANN has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,425°C (2,597 °F). N+T is the default condition FabDigit quotes; ANN is available on request or by drawing note.
Advantages
- High service temperature — 540°C (1,004 °F), better than 93% of steel grades
- Easy to machine — 63/100, better than 92% of steel grades
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
Limitations
- Low strength — 260 MPa (37.7 ksi), worse than 92% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
WC4-ANN properties
Typical room-temperature values for WC4-ANN; 22 are specific to this condition. Other listed values are WC4 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
WC4-ANN has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
WC4-ANN has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 92% of steel grades. Elongation at break is 28% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
WC4-ANN is rated for continuous service to 540°C (1,004 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
WC4-ANN conducts electricity at 8.1 % IACS, better than 61% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (14/100), better than 70% of steel grades.
Sustainability4
Producing a kilogram of WC4-ANN takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 75%.
Manufacturability8
WC4-ANN's machinability is good (63/100, better than 92% of steel grades); weldability good (62/100); formability poor (28/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with WC4-ANN
Is WC4 easy to machine?
Machines like N&T 4130/8620-class steel at ~60 % of 1212 — use rigid setups and carbide inserts, and expect a hard scale skin on as-cast surfaces.
Can WC4 be welded?
P-No.4-type Cr-Mo-Ni casting: preheat 175–260 °C, use E80xx-B2/Ni-Mo consumables, and PWHT at 620–680 °C for repairs and joints.
Can WC4 be formed, bent or molded?
Supplied only as sand/investment castings; design generous fillets and feed heavy sections to avoid shrinkage and hot tears, then normalize-and-temper.
What surface finishes work on WC4?
No anodizing; protect with epoxy/zinc-rich paint, phosphating or electroless nickel, and shot-blast castings before coating.
WC4 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 – 0.2 | 0.15 |
| Mn | 0.5 – 0.8 | 0.65 |
| Si | ≤ 0.6 | 0.35 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.02 |
| Ni | 0.7 – 1.1 | 0.9 |
| Cr | 0.5 – 0.8 | 0.65 |
| Mo | 0.45 – 0.65 | 0.55 |
| Curesidual element | ≤ 0.5 | — |
| Vresidual element | ≤ 0.03 | — |
| Wresidual element | ≤ 0.1 | — |
| Fetotal residual elements (Cu+V+W) ≤ 1.00 % per A217 | balance | — |
WC4-ANN — frequently asked
What is WC4-ANN used for?
WC4-ANN is typically used for valve bodies, high-pressure fittings and power plant castings. In short: ni-Cr-Mo pressure casting; stronger than carbon-moly grades; 540 °C service capability.
What is the yield strength of WC4-ANN?
WC4-ANN has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 92% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is WC4-ANN easy to machine?
Reasonably — machinability is rated good (63/100, better than 92% of steel grades). Machines like N&T 4130/8620-class steel at ~60 % of 1212 — use rigid setups and carbide inserts, and expect a hard scale skin on as-cast surfaces.
Can WC4-ANN be welded?
Yes — weldability is rated good (62/100). P-No.4-type Cr-Mo-Ni casting: preheat 175–260 °C, use E80xx-B2/Ni-Mo consumables, and PWHT at 620–680 °C for repairs and joints.
What surface finishes work on WC4-ANN?
No anodizing; protect with epoxy/zinc-rich paint, phosphating or electroless nickel, and shot-blast castings before coating.
Can WC4-ANN be formed, bent or molded?
Supplied only as sand/investment castings; design generous fillets and feed heavy sections to avoid shrinkage and hot tears, then normalize-and-temper.
What is the maximum service temperature of WC4-ANN?
WC4-ANN is rated for continuous use to about 540°C (1,004 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between WC4 N+T and WC4-ANN?
N+T is the default condition — standard supply condition for A217 WC4 pressure castings of ordinary section size. ANN: soft intermediate state used for rough machining or weld repair; not an A217 acceptance condition and must be re-normalized/tempered before service. Yield strength is 335 MPa in N+T versus 260 MPa in ANN.
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 — Material Properties (Metric) — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Steel Castings Handbook — Steel Founders' Society of America / ASM International (1995)
- ASME B16.34 — Valves: Flanged, Threaded, and Welding End — ASME (2020)
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.