Nickel Alloy M30H
UNS J24030 · ASTM A494 M30H
M30H is a higher-strength cast nickel-copper Monel-type alloy (UNS J24030, ASTM A494 M30H) that uses a raised silicon content for strengthening.
Reference datasheet — M30H 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 HT condition
M30H tempers and conditions
M30H is supplied in 3 conditions, soft to hard. HT is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition, used to ease rough machining of complex castings before final age hardening. | 300 | 540 | 25 | 180 HB | 3 % IACS |
As fabricated | Pick when only moderate strength is needed and the part will be machined before any aging. | 330 | 570 | 20 | 14 HRC | 2.7 % IACS |
HTDefault Solution treated and age hardened (≈595 °C precipitation treatment) per… | Standard commercial supply condition — full strength and hardness for pump/valve wear parts in seawater. | 520 | 740 | 15 | 30 HRC | — |
What is M30H?
M30H is a higher-strength cast nickel-copper Monel-type alloy (UNS J24030, ASTM A494 M30H) that uses a raised silicon content for strengthening. It is selected for marine propeller hubs, pump shaft sleeves and seawater valve trim where the standard M35 casting grades are too soft: heat treated it reaches 520 MPa yield, 740 MPa tensile, 15 % elongation and about 290 HB (30 HRC). The trade-offs are low elongation, a weldability rating of 25 with real hot-cracking risk, a machinability rating of 18 and a 480 °C service limit. Where weld repair or ductility matters more than strength, M30C or M35-2 is the nearer choice. M30H has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 52% of nickel alloy grades. It melts at 1,180°C (2,156 °F). M30H has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 76% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 172 GPa (24.9 Msi).
What is M30H used for?
- marine propeller hubs
- pump shaft sleeves
- seawater valve trim
Advantages
- High electrical conductivity — 2.5 % IACS, better than 85% of nickel alloy grades
- Low embodied carbon — 11 kg CO₂/kg, better than 85% of nickel alloy grades
- Conducts heat well — 17 W/m·K (9.82 BTU/hr·ft·°F), better than 84% of nickel alloy grades
- High strength — 520 MPa (75.4 ksi), better than 76% of nickel alloy grades
Limitations
- Low stiffness — 172 GPa (24.9 Msi), worse than 90% of nickel alloy grades
- Limited formability — 10/100, worse than 85% of nickel alloy grades
- Limited service temperature — 480°C (896 °F), worse than 82% of nickel alloy grades
- Difficult to weld — 25/100, worse than 82% of nickel alloy grades
- Limited ductility — 15%, worse than 81% of nickel alloy grades
M30H properties
Typical room-temperature values for M30H-HT; bars are the position among nickel alloy grades.
Physical3
M30H has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 52% of nickel alloy grades. It melts at 1,180°C (2,156 °F).
Mechanical13
M30H has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 76% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 172 GPa (24.9 Msi).
Thermal6
M30H is rated for continuous service to 480°C (896 °F). It conducts heat at 17 W/m·K (9.82 BTU/hr·ft·°F), better than 84% of nickel alloy grades. Thermal expansion is 13.7 µm/m·K (7.61 µin/in·°F).
Electrical3
M30H conducts electricity at 2.5 % IACS, better than 85% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 51% of nickel alloy grades.
Sustainability4
Producing a kilogram of M30H takes about 130 MJ of energy and emits 11 kg of CO₂ — less than 87% of nickel alloy grades. Typical recycled content is 40%.
Manufacturability8
M30H's machinability is poor (18/100, worse than 61% of nickel alloy grades); weldability poor (25/100); formability not recommended (10/100).
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 nickel alloy family
Yield strength against density for every nickel alloy grade FabDigit runs. M30H is highlighted; hover a dot for its name, or open the interactive family chart.
Working with M30H
Is M30H easy to machine?
Rough-machine in the solution-treated state; when aged use rigid setups, positive-rake carbide, low speed (~15–25 m/min) and heavy feed with flood coolant to beat work hardening and abrasive silicide.
Can M30H be welded?
Weld only when necessary — high Si makes the alloy hot-crack sensitive; preheat 150–260 °C, use Ni-Cu (ERNiCu-7 / Monel 60) filler, low heat input, and re-age after repair.
Can M30H be formed, bent or molded?
Sand or investment casting alloy with good fluidity from the Si content; feed heavy sections generously and allow ~2 % pattern shrinkage — it is not cold-formable.
M30H 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 |
|---|---|---|
| Cu | 27 – 33 | 30 |
| Siage-hardening element (Ni-Si precipitates) | 2.7 – 3.7 | 3.2 |
| Fe | ≤ 3.5 | 2 |
| Mn | ≤ 1.5 | 0.8 |
| C | ≤ 0.3 | 0.2 |
| S | ≤ 0.03 | 0.01 |
| Niremainder per ASTM A494; Ni + Co may be reported together | ≥ 60 (balance) |
What surface finishes work on M30H?
Pickle/passivate to remove casting scale; takes a good mechanical polish and accepts electroless nickel or hard chrome for extra wear resistance — anodizing does not apply.
Surface treatments FabDigit runs on nickel alloy 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).
Plating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Nickel Alloy M30H in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J24030
- ASTM
- A494 M30H
- Similar grades
- N05500
How much does M30H cost?
M30H is a high-cost nickel alloy ($$$$), pricier than about 78% 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.
M30H — frequently asked
What is M30H used for?
M30H is typically used for marine propeller hubs, pump shaft sleeves and seawater valve trim. In short: strongest cast Monel grade; si-hardened for wear duty; poor weldability, high strength.
What is the yield strength of M30H?
M30H has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 76% of nickel alloy grades. Strength varies by condition: see the 3 listed tempers.
Is M30H easy to machine?
Not especially — machinability is rated poor (18/100, worse than 61% of nickel alloy grades). Rough-machine in the solution-treated state; when aged use rigid setups, positive-rake carbide, low speed (~15–25 m/min) and heavy feed with flood coolant to beat work hardening and abrasive silicide.
Can M30H be welded?
Not readily — weldability is rated poor (25/100). Weld only when necessary — high Si makes the alloy hot-crack sensitive; preheat 150–260 °C, use Ni-Cu (ERNiCu-7 / Monel 60) filler, low heat input, and re-age after repair.
What surface finishes work on M30H?
Pickle/passivate to remove casting scale; takes a good mechanical polish and accepts electroless nickel or hard chrome for extra wear resistance — anodizing does not apply.
Can M30H be formed, bent or molded?
Sand or investment casting alloy with good fluidity from the Si content; feed heavy sections generously and allow ~2 % pattern shrinkage — it is not cold-formable.
What is the maximum service temperature of M30H?
M30H is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between M30H-HT and M30H-ST?
HT is the default condition — standard commercial supply condition — full strength and hardness for pump/valve wear parts in seawater. ST: softest condition, used to ease rough machining of complex castings before final age hardening. Yield strength is 520 MPa in HT versus 300 MPa in ST.
How much does M30H cost?
M30H is a high-cost nickel alloy ($$$$), pricier than about 78% 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 A494/A494M — Castings, Nickel and Nickel Alloy — ASTM International (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol. 15 — Casting (nickel alloy castings) — ASM International (2008)
- Nickel-copper (Monel-type) casting alloy datasheets — Nickel Institute / foundry producers (2020)
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.