Steel A897 Grade 3
ASTM A897 Grade 3 · EN EN-GJS-1050-6 · GB QTA1050-6
ASTM A897 Grade 3 is an austempered ductile iron (ADI) with an ausferrite matrix produced by salt-bath austempering, also designated EN-GJS-1050-6 and QTA1050-6.
Reference datasheet — A897 Grade 3 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 AT condition
A897 Grade 3 tempers and conditions
A897 Grade 3 is supplied in 3 conditions, soft to hard. AT is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Machining condition: alloyed ductile iron casting rough- and semi-finish machined in the soft state, then austempered to Grade 3 (allow ~0.05–0.1 % growth). | 400 | 620 | 10 | 16 HRC | 3.1 % IACS |
ATDefault Austempered to A897 Grade 3 | Standard as-supplied ADI Grade 3 condition: austenitized ~900 °C then salt-bath austempered ~315–345 °C; pick for gears, sprockets and wear parts needing 1050 MPa with usable ductility. | 810 | 1,120 | 8 | 36 HRC | — |
Austempered and shot peened | Shot peening after austempering induces strain-transformed martensite plus compressive residual stress; choose for gear roots and highly loaded fatigue parts. | 810 | 1,120 | 7 | 43 HRC | 2.7 % IACS |
What is A897 Grade 3?
ASTM A897 Grade 3 is an austempered ductile iron (ADI) with an ausferrite matrix produced by salt-bath austempering, also designated EN-GJS-1050-6 and QTA1050-6. It is specified where steel-level strength is wanted at casting cost and lower density: 1120 MPa tensile strength, 810 MPa yield, 8 % elongation and 340 HB (36 HRC), with good rolling-contact and abrasive wear resistance. Limits are a 300 °C maximum service temperature, a machinability score of 25 that pushes most cutting ahead of heat treatment, and no practical weldability after austempering. A897 Grade 5 is the choice when wear resistance outranks ductility. A897 Grade 3 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). A897 Grade 3 has a yield strength of 810 MPa (117 ksi) and a tensile strength of 1,120 MPa (162 ksi) — stronger than 87% of steel grades. Elongation at break is 8% and the elastic modulus is 168 GPa (24.4 Msi).
What is A897 Grade 3 used for?
- heavy truck gears
- differential housings
- mining equipment parts
Advantages
- High strength — 810 MPa (117 ksi), better than 87% of steel grades
Limitations
- Limited formability — 5/100, worse than 99% of steel grades
- Low stiffness — 168 GPa (24.4 Msi), worse than 97% of steel grades
- Low electrical conductivity — 2.7 % IACS, worse than 96% of steel grades
- Difficult to weld — 12/100, worse than 96% of steel grades
- Limited ductility — 8%, worse than 95% of steel grades
A897 Grade 3 properties
Typical room-temperature values for A897 Grade 3-AT; bars are the position among steel grades.
Physical3
A897 Grade 3 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).
Mechanical16
A897 Grade 3 has a yield strength of 810 MPa (117 ksi) and a tensile strength of 1,120 MPa (162 ksi) — stronger than 87% of steel grades. Elongation at break is 8% and the elastic modulus is 168 GPa (24.4 Msi).
Thermal6
A897 Grade 3 is rated for continuous service to 300°C (572 °F). It conducts heat at 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades. Thermal expansion is 13.5 µm/m·K (7.5 µin/in·°F).
Electrical3
A897 Grade 3 conducts electricity at 2.7 % IACS, worse than 96% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of A897 Grade 3 takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 80%.
Manufacturability8
A897 Grade 3's machinability is poor (25/100, worse than 93% of steel grades); weldability not recommended (12/100); 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. A897 Grade 3 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A897 Grade 3
Is A897 Grade 3 easy to machine?
Rough and finish machine in the as-cast/annealed state and allow for ~0.05–0.1 % growth during austempering; post-austempering cuts need CBN or ceramic inserts, rigid setups, low speed/high feed, and grinding for finish work.
Can A897 Grade 3 be welded?
Essentially not weldable in the austempered condition — heat destroys the ausferrite and forms martensite/carbides; if unavoidable, weld the ductile-iron blank with Ni electrodes before heat treatment.
Can A897 Grade 3 be formed, bent or molded?
Produced by green-sand or no-bake ductile-iron casting with tight nodularity (>85 %) and porosity control, then austenitized ~900 °C and salt-bath austempered ~315–345 °C for Grade 3 properties.
A897 Grade 3 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 |
|---|---|---|
| Cchemistry not fixed by A897; foundry sets it to meet mechanical properties | 3 – 3.9 | 3.6 |
| Si | 2 – 3 | 2.5 |
| Mnkept low in heavy sections to avoid segregation | 0.15 – 0.5 | 0.3 |
| Cuhardenability addition | 0.2 – 0.9 | 0.6 |
| Nihardenability, heavier sections | 0 – 2 | 0.5 |
| Mohardenability; excess causes carbide segregation | 0 – 0.3 | 0.2 |
| Mgnodulizer, residual | 0.03 – 0.06 | 0.04 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Fe | balance | — |
What surface finishes work on A897 Grade 3?
Not anodizable; protect with paint, e-coat, phosphate or oil. Shot peening greatly boosts fatigue life; avoid nitriding/plating processes exceeding ~300 °C.
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 A897 Grade 3 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- EN-GJS-1050-6
- GB (China)
- QTA1050-6
How much does A897 Grade 3 cost?
A897 Grade 3 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.
A897 Grade 3 — frequently asked
What is A897 Grade 3 used for?
A897 Grade 3 is typically used for heavy truck gears, differential housings and mining equipment parts. In short: steel strength at casting cost; strong-yet-ductile ADI grade; machine before austempering.
What is the yield strength of A897 Grade 3?
A897 Grade 3 has a typical yield strength of 810 MPa (117 ksi) and a tensile strength of 1,120 MPa (162 ksi) — stronger than 87% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is A897 Grade 3 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of steel grades). Rough and finish machine in the as-cast/annealed state and allow for ~0.05–0.1 % growth during austempering; post-austempering cuts need CBN or ceramic inserts, rigid setups, low speed/high feed, and grinding for finish work.
Can A897 Grade 3 be welded?
Not readily — weldability is rated not recommended (12/100). Essentially not weldable in the austempered condition — heat destroys the ausferrite and forms martensite/carbides; if unavoidable, weld the ductile-iron blank with Ni electrodes before heat treatment.
What surface finishes work on A897 Grade 3?
Not anodizable; protect with paint, e-coat, phosphate or oil. Shot peening greatly boosts fatigue life; avoid nitriding/plating processes exceeding ~300 °C.
Can A897 Grade 3 be formed, bent or molded?
Produced by green-sand or no-bake ductile-iron casting with tight nodularity (>85 %) and porosity control, then austenitized ~900 °C and salt-bath austempered ~315–345 °C for Grade 3 properties.
What is the maximum service temperature of A897 Grade 3?
A897 Grade 3 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A897 Grade 3-AT and A897 Grade 3-AC?
AT is the default condition — standard as-supplied ADI Grade 3 condition: austenitized ~900 °C then salt-bath austempered ~315–345 °C; pick for gears, sprockets and wear parts needing 1050 MPa with usable ductility. AC: machining condition: alloyed ductile iron casting rough- and semi-finish machined in the soft state, then austempered to Grade 3 (allow ~0.05–0.1 % growth). Yield strength is 810 MPa in AT versus 400 MPa in AC.
How much does A897 Grade 3 cost?
A897 Grade 3 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 A897/A897M — Standard Specification for Austempered Ductile Iron Castings — ASTM International (2016)
- EN 1564 — Founding: Ausferritic spheroidal graphite cast irons — CEN (2011)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Ductile Iron Data for Design Engineers (ADI section) — 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.