Steel A897 Grade 1 1050-750-07
Heat-treated state
ASTM A897 Grade 1 · EN EN-GJS-800-8 · GB QTA-800-8 · ISO 17804 JS/800-8
Choose for gears and crankshafts needing higher strength than Grade 1 while keeping ~7 % elongation.
Values for the 1050-750-07 condition
Other A897 Grade 1 tempers and conditions
A897 Grade 1 is listed in 8 conditions; see the grade overview at A897 Grade 1.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
austempered, highest-ductility grade | Highest austempering temperature (~385 °C): pick when impact toughness and machinability matter more than strength. | 550 | 800 | 13 | 26 HRC | — |
austempered | Tough general-purpose ADI class matching ISO 800-10 / EN-JS1100; good for suspension and agricultural parts needing high elongation. | 600 | 900 | 12 | 30 HRC | — |
900-650-09Default A897 Grade 1, austempered ~370 °C | The standard stocked ADI grade: best balance of ~900 MPa strength, 9–12 % elongation and high impact energy. | 700 | 950 | 11 | 32 HRC | — |
austempered | Intermediate strength/ductility class used where European ISO 1000-6 equivalence is required. | 760 | 1,100 | 8 | 35 HRC | — |
1050-750-07This page A897 Grade 2, austempered ~340 °C | Choose for gears and crankshafts needing higher strength than Grade 1 while keeping ~7 % elongation. | 820 | 1,120 | 8 | 36 HRC | — |
A897 Grade 3, austempered ~315 °C | High-strength gear/wear grade; strength and contact fatigue prioritised over impact toughness. | 920 | 1,280 | 5 | 41 HRC | — |
A897 Grade 4, austempered ~290 °C | Very high strength, low ductility — for heavily loaded gears, cams and abrasion-dominated parts. | 1,150 | 1,450 | 2.5 | 45 HRC | — |
A897 Grade 5, austempered ~260 °C | Maximum-hardness ADI for wear parts and ground engaging tools; essentially machined before heat treatment only. | 1,350 | 1,650 | 1.5 | 48 HRC | — |
What is A897 Grade 1 1050-750-07?
A897 Grade 1 1050-750-07 is A897 Grade 1 heat treated to 1050-750-07 — choose for gears and crankshafts needing higher strength than Grade 1 while keeping ~7 % elongation. A897 Grade 1 1050-750-07 has a yield strength of 820 MPa (119 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 165 GPa (23.9 Msi). A897 Grade 1 1050-750-07 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). 900-650-09 is the default condition FabDigit quotes; 1050-750-07 is available on request or by drawing note.
Advantages
- High strength — 820 MPa (119 ksi), better than 87% of steel grades
Limitations
- Limited formability — 5/100, worse than 99% of steel grades
- Low electrical conductivity — 2.2 % IACS, worse than 98% of steel grades
- Low stiffness — 165 GPa (23.9 Msi), worse than 97% of steel grades
- Limited ductility — 8%, worse than 95% of steel grades
- Poor heat conductor — 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades
A897 Grade 1 1050-750-07 properties
Typical room-temperature values for A897 Grade 1 1050-750-07; 12 are specific to this condition. Other listed values are A897 Grade 1 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A897 Grade 1 1050-750-07 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
A897 Grade 1 1050-750-07 has a yield strength of 820 MPa (119 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 165 GPa (23.9 Msi).
Thermal6
A897 Grade 1 1050-750-07 is rated for continuous service to 280°C (536 °F). It conducts heat at 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
A897 Grade 1 1050-750-07 conducts electricity at 2.2 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (18/100), better than 83% of steel grades.
Sustainability4
Producing a kilogram of A897 Grade 1 1050-750-07 takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 85%.
Manufacturability8
A897 Grade 1 1050-750-07's machinability is poor (28/100, worse than 91% of steel grades); weldability poor (15/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A897 Grade 1 1050-750-07
Is A897 Grade 1 easy to machine?
Machine in the as-cast (pearlitic/ferritic) state whenever possible; after austempering use rigid setups, negative-rake CBN or coated carbide at low speed and heavy feed — the strain-induced martensite from retained austenite work-hardens the cut surface.
Can A897 Grade 1 be welded?
Essentially not weldable in service condition — heat destroys the ausferrite; if unavoidable, weld before austempering with Ni-based electrodes and re-austemper the whole part.
Can A897 Grade 1 be formed, bent or molded?
Produced as sand/shell/lost-foam ductile iron castings with tight nodularity (>85 %), low carbide and porosity control; section size must suit the hardenability (Cu/Ni/Mo) so ausferrite forms throughout.
What surface finishes work on A897 Grade 1?
Shot peening adds large compressive stresses and can raise fatigue strength 30–50 %; protect with phosphate + paint, zinc-rich coating or electroless nickel — no anodizing (ferrous).
A897 Grade 1 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 A897 does not specify chemistry; typical base ductile iron for ADI | 3.2 – 3.9 | 3.6 |
| Si | 2.2 – 2.9 | 2.5 |
| Mnkept low in heavy sections to avoid segregation | 0.15 – 0.4 | 0.28 |
| Mgresidual, for nodularisation | 0.03 – 0.06 | 0.04 |
| Cuhardenability addition | 0 – 0.8 | 0.5 |
| Nihardenability, heavy sections | 0 – 2 | 0.5 |
| Mohardenability; excess promotes carbides | 0 – 0.3 | 0.15 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Fe | balance | — |
A897 Grade 1 1050-750-07 — frequently asked
What is A897 Grade 1 1050-750-07 used for?
A897 Grade 1 1050-750-07 is typically used for gears, crankshafts, suspension components, mining wear parts and tillage equipment. In short: steel-like strength, cast cost; ausferrite wear resistance; responds strongly to shot peening.
What is the yield strength of A897 Grade 1 1050-750-07?
A897 Grade 1 1050-750-07 has a typical yield strength of 820 MPa (119 ksi) and a tensile strength of 1,120 MPa (162 ksi) — stronger than 87% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is A897 Grade 1 1050-750-07 easy to machine?
Not especially — machinability is rated poor (28/100, worse than 91% of steel grades). Machine in the as-cast (pearlitic/ferritic) state whenever possible; after austempering use rigid setups, negative-rake CBN or coated carbide at low speed and heavy feed — the strain-induced martensite from retained austenite work-hardens the cut surface.
Can A897 Grade 1 1050-750-07 be welded?
Not readily — weldability is rated poor (15/100). Essentially not weldable in service condition — heat destroys the ausferrite; if unavoidable, weld before austempering with Ni-based electrodes and re-austemper the whole part.
What surface finishes work on A897 Grade 1 1050-750-07?
Shot peening adds large compressive stresses and can raise fatigue strength 30–50 %; protect with phosphate + paint, zinc-rich coating or electroless nickel — no anodizing (ferrous).
Can A897 Grade 1 1050-750-07 be formed, bent or molded?
Produced as sand/shell/lost-foam ductile iron castings with tight nodularity (>85 %), low carbide and porosity control; section size must suit the hardenability (Cu/Ni/Mo) so ausferrite forms throughout.
What is the maximum service temperature of A897 Grade 1 1050-750-07?
A897 Grade 1 1050-750-07 is rated for continuous use to about 280°C (536 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM A897/A897M-16 Standard Specification for Austempered Ductile Iron Castings — ASTM International (2016)
- ISO 17804 Founding — Ausferritic spheroidal graphite cast irons — Classification — ISO (2020)
- EN 1564 Founding — Ausferritic spheroidal graphite cast irons — CEN (2011)
- ASM Handbook Vol. 1: Properties and Selection: Irons, Steels, and High-Performance Alloys (ADI section) — ASM International (1990)
- ASM Handbook Vol. 15: Casting — ASM International (2008)
- Ductile Iron Data for Design Engineers (ADI chapter) — 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.