Steel G17NiCrMo13-6 +QT-high (+QT low-temper)
Hardness band
EN 1.6781
Lower tempering temperature when maximum strength/hardness is needed and toughness demands are moderate.
Values for the +QT-high condition
Other G17NiCrMo13-6 tempers and conditions
G17NiCrMo13-6 is listed in 9 conditions; see the grade overview at G17NiCrMo13-6.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest supply state for extensive rough machining before final hardening or case hardening. | 430 | 660 | 20 | 13 HRC | 6.5 % IACS |
Spheroidize annealed | Rough/blank supply for foundry-to-customer heat treatment; properties are non-uniform and not warranted. | 460 | 700 | 10 | 21 HRC | 6 % IACS |
Normalized and tempered | Lower-distortion alternative to Q&T for large or complex castings where full quench strength is not required. | 520 | 740 | 17 | 20 HRC | 6 % IACS |
Normalized | Grain-refined intermediate condition for castings that will be further machined and then hardened or carburised. | 540 | 780 | 14 | 22 HRC | 6 % IACS |
+QT | Same heat treatment on thick walls; property values fall with reduced quench rate — use for large housings and bases. | 590 | 780 | 15 | 22 HRC | 6 % IACS |
+QT low-temperature toughness variant | Higher tempering temperature and tighter melt cleanliness for cryogenic/offshore duty where sub-zero Charpy values are specified. | 620 | 790 | 18 | 23 HRC | 6 % IACS |
+QTDefault Quenched and tempered | Standard commercial delivery condition: best strength/toughness balance for gear, drum and heavy machinery castings. | 660 | 830 | 16 | 25 HRC | — |
Cold drawn | Choose for cast gear teeth, sprockets and track rollers needing a hard wear case over a tough Ni-Cr-Mo core. | 700 | 900 | 12 | 60 HRC | 6 % IACS |
+QT-highThis page +QT low-temper | Lower tempering temperature when maximum strength/hardness is needed and toughness demands are moderate. | 820 | 1,000 | 12 | 33 HRC | 6 % IACS |
What is G17NiCrMo13-6 +QT-high?
G17NiCrMo13-6 +QT-high is G17NiCrMo13-6 heat treated to +QT-high — lower tempering temperature when maximum strength/hardness is needed and toughness demands are moderate. G17NiCrMo13-6 +QT-high has a yield strength of 820 MPa (119 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 87% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi). G17NiCrMo13-6 +QT-high 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). +QT is the default condition FabDigit quotes; +QT-high is available on request or by drawing note.
Advantages
- High strength — 820 MPa (119 ksi), better than 87% of steel grades
Limitations
- Limited formability — 10/100, worse than 95% of steel grades
- Difficult to machine — 30/100, worse than 89% of steel grades
- Limited ductility — 12%, worse than 84% of steel grades
- Poor heat conductor — 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades
- Low electrical conductivity — 6 % IACS, worse than 78% of steel grades
G17NiCrMo13-6 +QT-high properties
Typical room-temperature values for G17NiCrMo13-6 +QT-high; 22 are specific to this condition. Other listed values are G17NiCrMo13-6 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
G17NiCrMo13-6 +QT-high 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
G17NiCrMo13-6 +QT-high has a yield strength of 820 MPa (119 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 87% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
G17NiCrMo13-6 +QT-high is rated for continuous service to 350°C (662 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
G17NiCrMo13-6 +QT-high conducts electricity at 6 % IACS, worse than 78% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (18/100), better than 83% of steel grades.
Sustainability4
Producing a kilogram of G17NiCrMo13-6 +QT-high takes about 30 MJ of energy and emits 2.4 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 75%.
Manufacturability8
G17NiCrMo13-6 +QT-high's machinability is poor (30/100, worse than 89% of steel grades); weldability poor (30/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with G17NiCrMo13-6 +QT-high
Is G17NiCrMo13-6 easy to machine?
Rough machine in the annealed or normalized state (carbide, 80–140 m/min); after Q&T at 250 HB use rigid setups, positive-rake coated carbide and generous coolant, and finish-grind carburised surfaces.
Can G17NiCrMo13-6 be welded?
Weldable with matched low-alloy Ni-Cr-Mo consumables under low-hydrogen conditions: preheat 200–250 °C, interpass control, and post-weld temper below the original tempering temperature; foundry weld repairs are best done before final heat treatment.
Can G17NiCrMo13-6 be formed, bent or molded?
Supplied as sand or investment castings — design for progressive solidification with generous fillets and risers; high Ni-Cr-Mo alloy needs low-S/P melt, degassing and full heat treatment to avoid coarse as-cast structure.
What surface finishes work on G17NiCrMo13-6?
Not anodizable; shot-blast then phosphate, zinc/nickel plating, thermal spray or paint. Bake after electroplating (190–220 °C) to avoid hydrogen embrittlement in high-strength conditions.
G17NiCrMo13-6 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 |
|---|---|---|
| Clow carbon for weld repair and carburising | 0.15 – 0.2 | 0.17 |
| Si | ≤ 0.6 | 0.4 |
| Mn | 0.55 – 0.9 | 0.7 |
| P | ≤ 0.02 | 0.01 |
| S | ≤ 0.02 | 0.01 |
| Cr | 1.3 – 1.8 | 1.5 |
| Nihardenability and low-temperature toughness | 3 – 3.8 | 3.3 |
| Mo | 0.2 – 0.5 | 0.35 |
| Vresidual | ≤ 0.05 | — |
| Fe | balance | — |
G17NiCrMo13-6 +QT-high — frequently asked
What is G17NiCrMo13-6 +QT-high used for?
G17NiCrMo13-6 +QT-high is typically used for gear and shaft castings, heavy machinery components and case-hardened structural castings. In short: case-hardenable cast steel; tough core after carburising; widest condition range.
What is the yield strength of G17NiCrMo13-6 +QT-high?
G17NiCrMo13-6 +QT-high has a typical yield strength of 820 MPa (119 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 87% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is G17NiCrMo13-6 +QT-high easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Rough machine in the annealed or normalized state (carbide, 80–140 m/min); after Q&T at 250 HB use rigid setups, positive-rake coated carbide and generous coolant, and finish-grind carburised surfaces.
Can G17NiCrMo13-6 +QT-high be welded?
Not readily — weldability is rated poor (30/100). Weldable with matched low-alloy Ni-Cr-Mo consumables under low-hydrogen conditions: preheat 200–250 °C, interpass control, and post-weld temper below the original tempering temperature; foundry weld repairs are best done before final heat treatment.
What surface finishes work on G17NiCrMo13-6 +QT-high?
Not anodizable; shot-blast then phosphate, zinc/nickel plating, thermal spray or paint. Bake after electroplating (190–220 °C) to avoid hydrogen embrittlement in high-strength conditions.
Can G17NiCrMo13-6 +QT-high be formed, bent or molded?
Supplied as sand or investment castings — design for progressive solidification with generous fillets and risers; high Ni-Cr-Mo alloy needs low-S/P melt, degassing and full heat treatment to avoid coarse as-cast structure.
What is the maximum service temperature of G17NiCrMo13-6 +QT-high?
G17NiCrMo13-6 +QT-high 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
- EN 10293 — Steel castings for general engineering uses — CEN (2015)
- EN 10340 — Steel castings for structural uses — CEN (2007)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys (steel castings) — ASM International (1990)
- Steel Castings Handbook — Steel Founders' Society of America / ASM (1995)
- Stahlschlüssel / Key to Steel — material 1.6781 — Verlag Stahlschlüssel Wegst (2019)
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.