Steel G30NiCrMo14 +QT1
Heat-treated state · default condition
EN 1.6771
+QT1 = quenched and tempered, lower strength class
Standard delivery condition for thick-section, highly stressed castings where toughness is prioritised over peak strength.
Values for the +QT1 condition
Other G30NiCrMo14 tempers and conditions
G30NiCrMo14 is listed in 3 conditions; see the grade overview at G30NiCrMo14.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for rough machining or straightening before the final quench-and-temper cycle. | 450 | 700 | 18 | 17 HRC | — |
+QT1DefaultThis page Quenched and tempered, lower strength class | Standard delivery condition for thick-section, highly stressed castings where toughness is prioritised over peak strength. | 750 | 920 | 14 | 28 HRC | — |
Quenched and tempered, higher strength class | Pick when maximum strength/weight is needed in moderate wall thickness and slightly lower impact energy is acceptable. | 860 | 1,020 | 12 | 33 HRC | — |
What is G30NiCrMo14 +QT1?
G30NiCrMo14 +QT1 is G30NiCrMo14 heat treated to +QT1 — standard delivery condition for thick-section, highly stressed castings where toughness is prioritised over peak strength. G30NiCrMo14 +QT1 has a yield strength of 750 MPa (109 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 84% of steel grades. Elongation at break is 14% and the elastic modulus is 208 GPa (30.2 Msi). G30NiCrMo14 +QT1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Advantages
- High strength — 750 MPa (109 ksi), better than 84% of steel grades
Limitations
- Limited formability — 10/100, worse than 95% of steel grades
- High embodied carbon — 2.5 kg CO₂/kg, worse than 82% of steel grades
- Low electrical conductivity — 5.7 % IACS, worse than 80% of steel grades
- Difficult to machine — 38/100, worse than 80% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
G30NiCrMo14 +QT1 properties
Typical room-temperature values for G30NiCrMo14 +QT1; 16 are specific to this condition. Other listed values are G30NiCrMo14 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
G30NiCrMo14 +QT1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
G30NiCrMo14 +QT1 has a yield strength of 750 MPa (109 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 84% of steel grades. Elongation at break is 14% and the elastic modulus is 208 GPa (30.2 Msi).
Thermal6
G30NiCrMo14 +QT1 is rated for continuous service to 350°C (662 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
G30NiCrMo14 +QT1 conducts electricity at 5.7 % IACS, worse than 80% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of G30NiCrMo14 +QT1 takes about 32 MJ of energy and emits 2.5 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 75%.
Manufacturability7
G30NiCrMo14 +QT1's machinability is fair (38/100, worse than 80% of steel grades); weldability poor (32/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with G30NiCrMo14 +QT1
Is G30NiCrMo14 easy to machine?
Rough machine in the annealed condition; in +QT1/+QT2 use rigid setups, coated carbide at 60–110 m/min with positive feed to cut under the work-hardened skin, and remove the sand-cast scale first.
Can G30NiCrMo14 be welded?
High carbon equivalent — use low-hydrogen matching or 2.5–3.5%Ni consumables, preheat 200–300 °C, maintain interpass, and stress-relieve/re-temper 30–50 °C below the original tempering temperature.
Can G30NiCrMo14 be formed, bent or molded?
Casting grade only: design generous risers and directional solidification, control section transitions to avoid hot tears, and normalise before the quench-and-temper cycle to refine coarse as-cast grain.
What surface finishes work on G30NiCrMo14?
No natural corrosion resistance — shot-blast then paint, zinc-rich primer, phosphate or hard-chrome/nickel plate; nitriding or induction hardening can be applied to running surfaces.
G30NiCrMo14 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 | 0.26 – 0.34 | 0.3 |
| Si | ≤ 0.6 | 0.4 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.02 | — |
| S | ≤ 0.02 | — |
| Cr | 1.2 – 1.5 | 1.35 |
| Mo | 0.25 – 0.55 | 0.4 |
| Nihigh Ni gives deep hardenability and low-temperature toughness | 3.2 – 3.8 | 3.5 |
| Vresidual/optional | ≤ 0.1 | — |
| Fe | balance | — |
G30NiCrMo14 +QT1 — frequently asked
What is G30NiCrMo14 +QT1 used for?
G30NiCrMo14 +QT1 is typically used for large forged/cast machinery components, heavy equipment structural castings and high-strength load-bearing parts. In short: high-nickel cast Ni-Cr-Mo; toughness in heavy sections; needs preheat to weld.
What is the yield strength of G30NiCrMo14 +QT1?
G30NiCrMo14 +QT1 has a typical yield strength of 750 MPa (109 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 84% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is G30NiCrMo14 +QT1 easy to machine?
Not especially — machinability is rated fair (38/100, worse than 80% of steel grades). Rough machine in the annealed condition; in +QT1/+QT2 use rigid setups, coated carbide at 60–110 m/min with positive feed to cut under the work-hardened skin, and remove the sand-cast scale first.
Can G30NiCrMo14 +QT1 be welded?
Not readily — weldability is rated poor (32/100). High carbon equivalent — use low-hydrogen matching or 2.5–3.5%Ni consumables, preheat 200–300 °C, maintain interpass, and stress-relieve/re-temper 30–50 °C below the original tempering temperature.
What surface finishes work on G30NiCrMo14 +QT1?
No natural corrosion resistance — shot-blast then paint, zinc-rich primer, phosphate or hard-chrome/nickel plate; nitriding or induction hardening can be applied to running surfaces.
Can G30NiCrMo14 +QT1 be formed, bent or molded?
Casting grade only: design generous risers and directional solidification, control section transitions to avoid hot tears, and normalise before the quench-and-temper cycle to refine coarse as-cast grain.
What is the maximum service temperature of G30NiCrMo14 +QT1?
G30NiCrMo14 +QT1 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.
Sources
- DIN 17205 — Quenched and tempered steel castings for general purposes (GS-30NiCrMo14, 1.6771) — DIN (1992)
- EN 10340 — Steel castings for structural uses — CEN (2007)
- ISO 18265 — Metallic materials: conversion of hardness values — ISO (2013)
- 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.