Steel G25NiCrMo3 +QT1
Heat-treated state · default condition
EN 1.6553
+QT1 = quenched and tempered, lower strength / higher toughness condition
Standard supply condition for general machinery castings needing a balance of ~500 MPa yield with good impact toughness in thick sections.
Values for the +QT1 condition
Other G25NiCrMo3 tempers and conditions
G25NiCrMo3 is listed in 4 conditions; see the grade overview at G25NiCrMo3.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition, used to ease rough machining of complex castings before the final quench-and-temper cycle. | 340 | 570 | 22 | 165 HB | — |
Normalized | Intermediate-strength, low-cost condition for lightly stressed castings or as a stage before final quench and temper. | 420 | 660 | 17 | 13 HRC | — |
+QT1DefaultThis page Quenched and tempered, lower strength / higher toughness condition | Standard supply condition for general machinery castings needing a balance of ~500 MPa yield with good impact toughness in thick sections. | 550 | 780 | 14 | 21 HRC | — |
Quenched and tempered, higher strength condition | Choose when higher yield strength (~700 MPa) and wear resistance are needed and section thickness/impact demands are moderate. | 720 | 920 | 10 | 28 HRC | — |
What is G25NiCrMo3 +QT1?
G25NiCrMo3 +QT1 is G25NiCrMo3 heat treated to +QT1 — standard supply condition for general machinery castings needing a balance of ~500 MPa yield with good impact toughness in thick sections. G25NiCrMo3 +QT1 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 71% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). G25NiCrMo3 +QT1 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F).
Limitations
- Limited formability — 12/100, worse than 92% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
G25NiCrMo3 +QT1 properties
Typical room-temperature values for G25NiCrMo3 +QT1; 17 are specific to this condition. Other listed values are G25NiCrMo3 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
G25NiCrMo3 +QT1 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
G25NiCrMo3 +QT1 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 71% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
G25NiCrMo3 +QT1 is rated for continuous service to 400°C (752 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
G25NiCrMo3 +QT1 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of G25NiCrMo3 +QT1 takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 75%.
Manufacturability8
G25NiCrMo3 +QT1's machinability is fair (45/100, worse than 65% of steel grades); weldability fair (45/100); formability not recommended (12/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with G25NiCrMo3 +QT1
Is G25NiCrMo3 easy to machine?
Machine in the annealed or normalized state where possible; at 230–280 HB use rigid setups, coated carbide, moderate speeds and watch for hard skin/sand inclusions on unfettled surfaces.
Can G25NiCrMo3 be welded?
Weldable with low-hydrogen electrodes or MIG matching filler; preheat 200–300 °C depending on section, maintain interpass, and re-temper below the original tempering temperature after welding.
Can G25NiCrMo3 be formed, bent or molded?
Supplied as sand or shell castings — no cold forming; design with generous fillets, uniform sections and adequate risering to avoid shrinkage porosity in the heavier Ni-Cr-Mo sections.
What surface finishes work on G25NiCrMo3?
Not anodizable; protect by shot blasting plus paint, phosphate-and-oil, zinc or nickel plating, or nitriding/induction hardening where local wear resistance is needed.
G25NiCrMo3 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 | 0.2 – 0.3 | 0.25 |
| Si | ≤ 0.6 | 0.4 |
| Mn | 0.5 – 0.9 | 0.7 |
| Pmax, foundry practice | ≤ 0.02 | 0.02 |
| Smax, foundry practice | ≤ 0.02 | 0.01 |
| Cr | 0.35 – 0.7 | 0.5 |
| Ni | 0.6 – 1 | 0.8 |
| Mo | 0.15 – 0.3 | 0.22 |
| Fe | balance | — |
G25NiCrMo3 +QT1 — frequently asked
What is G25NiCrMo3 +QT1 used for?
G25NiCrMo3 +QT1 is typically used for gearbox housings, machinery frames and heavy equipment structural castings. In short: hardenable Ni-Cr-Mo casting; 550 MPa cast yield; needs preheat to weld.
What is the yield strength of G25NiCrMo3 +QT1?
G25NiCrMo3 +QT1 has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 71% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is G25NiCrMo3 +QT1 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in the annealed or normalized state where possible; at 230–280 HB use rigid setups, coated carbide, moderate speeds and watch for hard skin/sand inclusions on unfettled surfaces.
Can G25NiCrMo3 +QT1 be welded?
With care — weldability is rated fair (45/100). Weldable with low-hydrogen electrodes or MIG matching filler; preheat 200–300 °C depending on section, maintain interpass, and re-temper below the original tempering temperature after welding.
What surface finishes work on G25NiCrMo3 +QT1?
Not anodizable; protect by shot blasting plus paint, phosphate-and-oil, zinc or nickel plating, or nitriding/induction hardening where local wear resistance is needed.
Can G25NiCrMo3 +QT1 be formed, bent or molded?
Supplied as sand or shell castings — no cold forming; design with generous fillets, uniform sections and adequate risering to avoid shrinkage porosity in the heavier Ni-Cr-Mo sections.
What is the maximum service temperature of G25NiCrMo3 +QT1?
G25NiCrMo3 +QT1 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.
Sources
- EN 10293 — Steel castings for general engineering uses — CEN (2015)
- EN 10340 — Steel castings for structural uses — CEN (2007)
- EN 10027-2 — Designation systems for steels: numerical system — CEN (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
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.