Steel GX15CrMo9-1
ASTM A217 Gr. C12 · EN 1.7376
GX15CrMo9-1 (1.7376) is a 9Cr-1Mo cast alloy steel, the casting counterpart of wrought P9 and equivalent to ASTM A217 Gr.
Reference datasheet — GX15CrMo9-1 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 +NT condition
GX15CrMo9-1 tempers and conditions
GX15CrMo9-1 is supplied in 4 conditions, soft to hard. +NT is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Soft ferrite+carbide condition for rough machining or repair welding of castings; must be re-normalized and tempered before pressure service. | 255 | 470 | 24 | 160 HB | 3.2 % IACS |
+NTDefault Normalized and tempered | Standard pressure-part condition: normalize ~1040–1080 °C, temper ≥730 °C for creep strength plus code-compliant ductility. | 320 | 520 | 20 | 185 HB | — |
Quenched and tempered | Choose for heavy-section castings where accelerated cooling is needed to obtain uniform tempered martensite and higher yield strength. | 385 | 570 | 18 | 205 HB | — |
As fabricated | Non-code condition seen only between pouring and heat treatment: hard, brittle as-quenched martensite; never supplied for pressure duty. | 500 | 700 | 7 | 31 HRC | 3 % IACS |
What is GX15CrMo9-1?
GX15CrMo9-1 (1.7376) is a 9Cr-1Mo cast alloy steel, the casting counterpart of wrought P9 and equivalent to ASTM A217 Gr. C12. It is chosen for elevated-temperature pressure castings running to 600 °C — valve bodies, fittings and housings — with 320 MPa yield, 520 MPa tensile, 20 % elongation and about 185 HB in the tempered condition. The limits are processing and protection: 200–300 °C preheat with mandatory 730–760 °C PWHT, modest machinability (42) and no inherent corrosion resistance (score 30), so bare surfaces must be coated. G17CrMo9-10 (WC9) is the usual lower-cost choice below 550 °C. GX15CrMo9-1 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,450°C (2,642 °F). GX15CrMo9-1 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 81% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
What is GX15CrMo9-1 used for?
- high-temperature valve bodies
- power plant fittings
- petrochemical pressure castings
Advantages
- High service temperature — 600°C (1,112 °F), better than 98% of steel grades
- Good corrosion resistance — 30/100, better than 95% of steel grades
Limitations
- Low electrical conductivity — 3.1 % IACS, worse than 89% of steel grades
- Limited formability — 15/100, worse than 87% of steel grades
- Poor heat conductor — 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 86% of steel grades
- Low strength — 320 MPa (46.4 ksi), worse than 81% of steel grades
GX15CrMo9-1 properties
Typical room-temperature values for GX15CrMo9-1-+NT; bars are the position among steel grades.
Physical3
GX15CrMo9-1 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical16
GX15CrMo9-1 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 81% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
GX15CrMo9-1 is rated for continuous service to 600°C (1,112 °F). It conducts heat at 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 86% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
GX15CrMo9-1 conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (30/100), better than 95% of steel grades.
Sustainability4
Producing a kilogram of GX15CrMo9-1 takes about 33 MJ of energy and emits 2.4 kg of CO₂ — more than 76% of steel grades. Typical recycled content is 70%.
Manufacturability8
GX15CrMo9-1's machinability is fair (42/100, worse than 73% of steel grades); weldability fair (40/100); formability poor (15/100).
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. GX15CrMo9-1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with GX15CrMo9-1
Is GX15CrMo9-1 easy to machine?
Machine in the tempered condition with rigid setups, coated carbide and moderate speeds; remove the abrasive cast skin first and expect work hardening near 200 HB.
Can GX15CrMo9-1 be welded?
Weldable with matching 9Cr-1Mo (E505/ER80S-B8) consumables using 200–300 °C preheat, controlled interpass and mandatory 730–760 °C PWHT to avoid hard, crack-prone martensite.
Can GX15CrMo9-1 be formed, bent or molded?
Supplied as sand or investment castings only — no cold forming; design generous fillets and directional feeding, and control cooling to prevent quench cracks in heavy sections.
GX15CrMo9-1 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 |
|---|---|---|
| CEN 10213 GX15CrMo9-1; ASTM A217 C12 allows 0.20 max | 0.08 – 0.2 | 0.15 |
| SiEN often limits ≤0.60 | ≤ 1 | 0.5 |
| Mn | 0.35 – 0.7 | 0.5 |
| PA217: 0.040 max | ≤ 0.03 | |
| SA217: 0.045 max | ≤ 0.02 | |
| Cr | 8 – 10 | 9 |
| Mo | 0.9 – 1.2 | 1 |
| Niresidual | ≤ 0.4 | |
| Fe | balance |
What surface finishes work on GX15CrMo9-1?
Not anodizable; shot blast and use high-temperature aluminum/silicone paint or aluminizing for atmospheric protection, and machined seats for valve sealing surfaces.
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 GX15CrMo9-1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A217 Gr. C12
- EN / DIN / Werkstoff-Nr.
- 1.7376
How much does GX15CrMo9-1 cost?
GX15CrMo9-1 is a premium-cost steel ($$$), cheaper than about 51% 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.
GX15CrMo9-1 — frequently asked
What is GX15CrMo9-1 used for?
GX15CrMo9-1 is typically used for high-temperature valve bodies, power plant fittings and petrochemical pressure castings. In short: cast equivalent of P9; 600 °C pressure service; highest-temperature CrMo casting.
What is the yield strength of GX15CrMo9-1?
GX15CrMo9-1 has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 81% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is GX15CrMo9-1 easy to machine?
Not especially — machinability is rated fair (42/100, worse than 73% of steel grades). Machine in the tempered condition with rigid setups, coated carbide and moderate speeds; remove the abrasive cast skin first and expect work hardening near 200 HB.
Can GX15CrMo9-1 be welded?
With care — weldability is rated fair (40/100). Weldable with matching 9Cr-1Mo (E505/ER80S-B8) consumables using 200–300 °C preheat, controlled interpass and mandatory 730–760 °C PWHT to avoid hard, crack-prone martensite.
What surface finishes work on GX15CrMo9-1?
Not anodizable; shot blast and use high-temperature aluminum/silicone paint or aluminizing for atmospheric protection, and machined seats for valve sealing surfaces.
Can GX15CrMo9-1 be formed, bent or molded?
Supplied as sand or investment castings only — no cold forming; design generous fillets and directional feeding, and control cooling to prevent quench cracks in heavy sections.
What is the maximum service temperature of GX15CrMo9-1?
GX15CrMo9-1 is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between GX15CrMo9-1 +NT and GX15CrMo9-1-F?
+NT is the default condition — standard pressure-part condition: normalize ~1040–1080 °C, temper ≥730 °C for creep strength plus code-compliant ductility. F: non-code condition seen only between pouring and heat treatment: hard, brittle as-quenched martensite; never supplied for pressure duty. Yield strength is 320 MPa in +NT versus 500 MPa in F.
How much does GX15CrMo9-1 cost?
GX15CrMo9-1 is a premium-cost steel ($$$), cheaper than about 51% 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 A217/A217M — Steel Castings, Martensitic Stainless and Alloy, for Pressure-Containing Parts (Gr. C12) — ASTM International (2021)
- EN 10213 — Steel castings for pressure purposes (GX15CrMo9-1, 1.7376) — CEN (2016)
- ASME BPVC Section II Part D — Material properties (9Cr-1Mo) — ASME (2023)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- GB/T 16253 — (ZG1Cr9Mo class) — SAC (2019)
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.