Steel Ductile Iron As Cast
Finish state · default condition
also Nodular Iron, Nodular Cast Iron
Default stocked condition: best cost/strength balance for general machinery castings, housings and brackets.
Values for the As Cast condition
Other Ductile Iron tempers and conditions
Ductile Iron is listed in 6 conditions; see the grade overview at Ductile Iron.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
fully ferritic (ASTM A536 60-40-18 / EN GJS-400-18) | Pick when maximum ductility, impact energy and low-temperature toughness matter — pressure pipe, fittings, wind-turbine and safety-critical castings. | 300 | 440 | 20 | 160 HB | 36 W/m·K |
sub-critical stress relief (≈540–650 °C), matrix essentially as-cast | Pick for dimensionally critical machined castings (hydraulic bodies, machine bases) where residual casting stress must be removed without changing strength class. | 320 | 460 | 15 | 180 HB | 3.1 % IACS |
As CastDefaultThis page ferritic/pearlitic matrix, no heat treatment (ASTM A536 65-45-12 / EN GJS-450-10) | Default stocked condition: best cost/strength balance for general machinery castings, housings and brackets. | 340 | 480 | 14 | 187 HB | 33 W/m·K |
Normalized and tempered | Pick for higher strength and wear resistance with moderate ductility — gears, crankshafts, sprockets, heavy-duty linkages. | 510 | 730 | 5 | 25 HRC | 30 W/m·K |
Quenched and tempered | Pick for maximum strength and wear life in ductile iron where low elongation is acceptable — dies, rolls, high-load gears and pins. | 700 | 900 | 3 | 34 HRC | 26 W/m·K |
Austempered ductile iron, ausferrite matrix | Pick when you want steel-level strength and fatigue life plus useful ductility and wear resistance at casting cost — suspension arms, track links, gears, ground-engaging tools. | 750 | 1,050 | 7 | 35 HRC | 24 W/m·K |
What is Ductile Iron As Cast?
Ductile Iron As Cast is Ductile Iron supplied in the As Cast condition — default stocked condition: best cost/strength balance for general machinery castings, housings and brackets. Ductile Iron As Cast has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 76% of steel grades. Elongation at break is 14% and the elastic modulus is 169 GPa (24.5 Msi). Ductile Iron As Cast has a density of 7.1 g/cm³ (0.257 lb/in³), lighter than 99% of steel grades. It melts at 1,150°C (2,102 °F).
Advantages
- Easy to machine — 68/100, better than 95% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Low stiffness — 169 GPa (24.5 Msi), worse than 97% of steel grades
- Limited formability — 8/100, worse than 97% of steel grades
- Low fracture toughness — 42 MPa·√m (38.2 ksi·√in), worse than 92% of steel grades
- Low electrical conductivity — 3.1 % IACS, worse than 89% of steel grades
- Poor heat conductor — 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades
Ductile Iron As Cast properties
Typical room-temperature values for Ductile Iron As Cast; 15 are specific to this condition. Other listed values are Ductile Iron reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
Ductile Iron As Cast has a density of 7.1 g/cm³ (0.257 lb/in³), lighter than 99% of steel grades. It melts at 1,150°C (2,102 °F).
Mechanical15
Ductile Iron As Cast has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 76% of steel grades. Elongation at break is 14% and the elastic modulus is 169 GPa (24.5 Msi).
Thermal6
Ductile Iron As Cast is rated for continuous service to 400°C (752 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Ductile Iron As Cast conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (16/100), better than 79% of steel grades.
Sustainability4
Producing a kilogram of Ductile Iron As Cast takes about 21 MJ of energy and emits 1.9 kg of CO₂ — less than 99% of steel grades. Typical recycled content is 85%.
Manufacturability8
Ductile Iron As Cast's machinability is good (68/100, better than 95% of steel grades); weldability fair (35/100); formability not recommended (8/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Ductile Iron As Cast
Is Ductile Iron easy to machine?
Machines better than steel of equal hardness — carbide at 150–300 m/min for ferritic/pearlitic grades, dry or with light coolant; watch for hard carbides in thin chilled sections and use CBN on Q&T/ADI.
Can Ductile Iron be welded?
Poor as-welded: use Ni or Ni-Fe electrodes (ENiFe-CI), 200–350 °C preheat, short low-heat beads with peening, then ferritize/stress-relieve to avoid carbides and martensite in the HAZ.
Can Ductile Iron be formed, bent or molded?
A casting alloy — green sand, shell, no-bake or permanent mold with Mg treatment plus late inoculation; feed for shrinkage and keep section modulus consistent since nodule count and matrix are section-sensitive, and it is not cold formed.
What surface finishes work on Ductile Iron?
No anodizing; shot blast then paint, powder coat, zinc/phosphate or electroless nickel; cement-mortar or fusion-bonded epoxy lining for water pipe; can be flame/induction hardened or nitrided for wear surfaces.
Ductile Iron 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 |
|---|---|---|
| Ctotal carbon; CE typically 4.3–4.6 | 3.2 – 3.9 | 3.6 |
| Sihigher Si strengthens ferrite, lowers toughness | 1.8 – 2.9 | 2.4 |
| Mnkept low for ferritic grades | 0.1 – 0.6 | 0.3 |
| Mgresidual Mg for nodularization | 0.03 – 0.06 | 0.04 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.02 | 0.01 |
| Cuoptional pearlite stabilizer (higher-strength grades) | 0 – 0.8 | 0.2 |
| Nioptional, hardenability/toughness | 0 – 1 | |
| Mooptional, for ADI/Q&T sections | 0 – 0.4 | |
| Fe | balance |
Ductile Iron As Cast — frequently asked
What is Ductile Iron As Cast used for?
Ductile Iron As Cast is typically used for water and sewer pressure pipe and fittings, valve and pump housings, engine blocks and crankshafts, gearbox housings and gears, wheel hubs and steering knuckles and machine tool bases and heavy brackets. In short: stronger than gray iron.
What is the yield strength of Ductile Iron As Cast?
Ductile Iron As Cast has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 76% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is Ductile Iron As Cast easy to machine?
Reasonably — machinability is rated good (68/100, better than 95% of steel grades). Machines better than steel of equal hardness — carbide at 150–300 m/min for ferritic/pearlitic grades, dry or with light coolant; watch for hard carbides in thin chilled sections and use CBN on Q&T/ADI.
Can Ductile Iron As Cast be welded?
With care — weldability is rated fair (35/100). Poor as-welded: use Ni or Ni-Fe electrodes (ENiFe-CI), 200–350 °C preheat, short low-heat beads with peening, then ferritize/stress-relieve to avoid carbides and martensite in the HAZ.
What surface finishes work on Ductile Iron As Cast?
No anodizing; shot blast then paint, powder coat, zinc/phosphate or electroless nickel; cement-mortar or fusion-bonded epoxy lining for water pipe; can be flame/induction hardened or nitrided for wear surfaces.
Can Ductile Iron As Cast be formed, bent or molded?
A casting alloy — green sand, shell, no-bake or permanent mold with Mg treatment plus late inoculation; feed for shrinkage and keep section modulus consistent since nodule count and matrix are section-sensitive, and it is not cold formed.
What is the maximum service temperature of Ductile Iron As Cast?
Ductile Iron As Cast is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Ductile Iron As Cast and Ductile Iron-ADI?
As Cast is the default condition — default stocked condition: best cost/strength balance for general machinery castings, housings and brackets. ADI: pick when you want steel-level strength and fatigue life plus useful ductility and wear resistance at casting cost — suspension arms, track links, gears, ground-engaging tools. Yield strength is 340 MPa in As Cast versus 750 MPa in ADI.
Can FabDigit make parts in Ductile Iron As Cast?
Yes — Ductile Iron As Cast is available for CNC machining and casting & forging; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A536 — Standard Specification for Ductile Iron Castings — ASTM International (2019)
- ASTM A897/A897M — Austempered Ductile Iron Castings — ASTM International (2022)
- EN 1563 — Founding: Spheroidal graphite cast irons — CEN (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Ductile Iron Data for Design Engineers — Ductile Iron Society / Rio Tinto Iron & Titanium (2013)
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.