Steel A536 120-90-02
ASTM A536 120-90-02 · EN EN-GJS-900-2, 0.7090 · JIS FCD900 · GB QT900-2
ASTM A536 120-90-02 is the highest-strength conventional (non-austempered) ductile iron, with a pearlitic to tempered-martensitic matrix, also designated QT900-2, FCD900, EN-GJS-900-2 and 0.7090.
Reference datasheet — A536 120-90-02 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 QT condition
A536 120-90-02 tempers and conditions
A536 120-90-02 is supplied in 4 conditions, soft to hard. QT 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 |
|---|---|---|---|---|---|---|
Normalized and tempered | Used for large or crack-sensitive sections where oil quenching risks distortion; needs Cu/Mo/Ni alloying to reach the 120-90-02 minima. | 640 | 880 | 3 | 30 HRC | 2.7 % IACS |
QTDefault Quenched and tempered | Standard commercial route for 120-90-02: austenitize ~900 °C, oil quench, temper 500–600 °C to hit 827/621 MPa with 2 % elongation. | 660 | 900 | 3 | 32 HRC | 2.7 % IACS |
Q&T core plus induction/flame hardened surface | Choose for gear teeth, journals and cam lobes needing a hard wear surface over a tough 120-90-02 core. | 660 | 900 | 2 | 54 HRC | 2.6 % IACS |
Quenched and low-temperature tempered, high hardness | Pick when wear resistance dominates and elongation near the 2 % minimum is acceptable (gears, cams, dies). | 750 | 1,000 | 2 | 39 HRC | 2.5 % IACS |
What is A536 120-90-02?
ASTM A536 120-90-02 is the highest-strength conventional (non-austempered) ductile iron, with a pearlitic to tempered-martensitic matrix, also designated QT900-2, FCD900, EN-GJS-900-2 and 0.7090. It is used where a casting must carry high contact and bending loads: 900 MPa tensile strength, 660 MPa yield, 3 % elongation and 302 HB (32 HRC). The trade-offs are 3 % elongation, a machinability score of 35, quench distortion risk during Q&T, 350 °C maximum service and repair-only welding. Austempered ductile iron (A897 Grade 3) is the next step for higher strength with better toughness. A536 120-90-02 has a density of 7.1 g/cm³ (0.257 lb/in³), lighter than 99% of steel grades. It melts at 1,140°C (2,084 °F). A536 120-90-02 has a yield strength of 660 MPa (95.7 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 80% of steel grades. Elongation at break is 3% and the elastic modulus is 172 GPa (24.9 Msi).
What is A536 120-90-02 used for?
- gears
- camshafts
- wear plates
- high-load machine components
Advantages
- Low embodied carbon — 1.8 kg CO₂/kg, better than 99% of steel grades
- High strength — 660 MPa (95.7 ksi), better than 80% of steel grades
Limitations
- Limited ductility — 3%, worse than 99% of steel grades
- Limited formability — 5/100, worse than 99% of steel grades
- Low stiffness — 172 GPa (24.9 Msi), worse than 96% of steel grades
- Low electrical conductivity — 2.7 % IACS, worse than 96% of steel grades
- Low fracture toughness — 35 MPa·√m (31.9 ksi·√in), worse than 94% of steel grades
A536 120-90-02 properties
Typical room-temperature values for A536 120-90-02-QT; bars are the position among steel grades.
Physical3
A536 120-90-02 has a density of 7.1 g/cm³ (0.257 lb/in³), lighter than 99% of steel grades. It melts at 1,140°C (2,084 °F).
Mechanical16
A536 120-90-02 has a yield strength of 660 MPa (95.7 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 80% of steel grades. Elongation at break is 3% and the elastic modulus is 172 GPa (24.9 Msi).
Thermal6
A536 120-90-02 is rated for continuous service to 350°C (662 °F). It conducts heat at 32 W/m·K (18.5 BTU/hr·ft·°F), worse than 82% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
A536 120-90-02 conducts electricity at 2.7 % IACS, worse than 96% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (16/100), better than 79% of steel grades.
Sustainability4
Producing a kilogram of A536 120-90-02 takes about 21 MJ of energy and emits 1.8 kg of CO₂ — less than 99% of steel grades. Typical recycled content is 85%.
Manufacturability7
A536 120-90-02's machinability is fair (35/100, worse than 84% of steel grades); weldability poor (18/100); formability not recommended (5/100).
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. A536 120-90-02 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A536 120-90-02
Is A536 120-90-02 easy to machine?
Rough machine before hardening where possible; after Q&T use rigid setups, negative-rake coated carbide or CBN at low feed — hardness 269–341 HB cuts tool life sharply versus 65-45-12.
Can A536 120-90-02 be welded?
Essentially repair-only: preheat 300–400 °C, NiFe (ENiFe-CI) electrodes, short stringer beads, peening and slow cool, then re-temper to avoid brittle martensitic HAZ.
Can A536 120-90-02 be formed, bent or molded?
Green sand or shell mould casting with Mg treatment and inoculation; provide generous risering and controlled section change, then austenitize–quench in oil with fixtures to limit distortion and quench cracking.
A536 120-90-02 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 |
|---|---|---|
| CASTM A536 does not specify chemistry; typical foundry practice | 3.2 – 3.9 | 3.6 |
| Si | 2 – 2.8 | 2.4 |
| Mnhigher Mn aids hardenability | 0.2 – 0.8 | 0.5 |
| Mgresidual, for nodularization | 0.03 – 0.06 | 0.04 |
| Cupearlite/hardenability promoter | 0.4 – 1 | 0.7 |
| Nioptional, heavy sections | 0 – 1 | 0.3 |
| Mooptional, heavy sections | 0.1 – 0.5 | 0.25 |
| Pimpurity limit | ≤ 0.05 | 0.03 |
| Simpurity limit | ≤ 0.02 | 0.01 |
| Fe | balance | — |
What surface finishes work on A536 120-90-02?
Shot blast then paint, phosphate or zinc-rich primer for corrosion; can be nitrided, induction hardened or hard chrome plated — nodules leave micro-pits so mirror polish is limited.
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 A536 120-90-02 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- EN-GJS-900-20.7090
- GB (China)
- QT900-2
- JIS
- FCD900
How much does A536 120-90-02 cost?
A536 120-90-02 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.
A536 120-90-02 — frequently asked
What is A536 120-90-02 used for?
A536 120-90-02 is typically used for gears, camshafts, wear plates and high-load machine components. In short: strongest standard ductile iron; wear-resistant hardened matrix; low ductility, hard to machine.
What is the yield strength of A536 120-90-02?
A536 120-90-02 has a typical yield strength of 660 MPa (95.7 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 80% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is A536 120-90-02 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Rough machine before hardening where possible; after Q&T use rigid setups, negative-rake coated carbide or CBN at low feed — hardness 269–341 HB cuts tool life sharply versus 65-45-12.
Can A536 120-90-02 be welded?
Not readily — weldability is rated poor (18/100). Essentially repair-only: preheat 300–400 °C, NiFe (ENiFe-CI) electrodes, short stringer beads, peening and slow cool, then re-temper to avoid brittle martensitic HAZ.
What surface finishes work on A536 120-90-02?
Shot blast then paint, phosphate or zinc-rich primer for corrosion; can be nitrided, induction hardened or hard chrome plated — nodules leave micro-pits so mirror polish is limited.
Can A536 120-90-02 be formed, bent or molded?
Green sand or shell mould casting with Mg treatment and inoculation; provide generous risering and controlled section change, then austenitize–quench in oil with fixtures to limit distortion and quench cracking.
What is the maximum service temperature of A536 120-90-02?
A536 120-90-02 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 A536 120-90-02-QT and A536 120-90-02 QT-HH?
QT is the default condition — standard commercial route for 120-90-02: austenitize ~900 °C, oil quench, temper 500–600 °C to hit 827/621 MPa with 2 % elongation. QT-HH: pick when wear resistance dominates and elongation near the 2 % minimum is acceptable (gears, cams, dies). Yield strength is 660 MPa in QT versus 750 MPa in QT-HH.
How much does A536 120-90-02 cost?
A536 120-90-02 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
- ASTM A536 Standard Specification for Ductile Iron Castings — ASTM International (2019)
- 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; 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.