Stainless Steel N-155 (Multimet)-SA (Solution annealed)
Heat-treated state · default condition
UNS R30155 · also Multimet
Standard stocked condition for sheet, plate, bar and forgings; best ductility and formability, and the condition from which parts are welded and formed.
Values for the SA condition
Other N-155 (Multimet) tempers and conditions
N-155 (Multimet) is listed in 6 conditions; see the grade overview at N-155 (Multimet).
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefaultThis page Solution annealed | Standard stocked condition for sheet, plate, bar and forgings; best ductility and formability, and the condition from which parts are welded and formed. | 415 | 815 | 45 | 200 HB | — |
As-welded deposit | Typical joint properties for fabricated combustion-liner and duct hardware welded in the solution-annealed condition. | 430 | 760 | 25 | 14 HRC | 1.9 % IACS |
Hot rolled | As-hot-worked bar and plate where subsequent solution treatment will be done by the part maker, or where moderate strength suffices. | 500 | 880 | 35 | 20 HRC | 1.9 % IACS |
solution annealed then aged ≈730–760 °C / 16 h | Choose when higher room- and elevated-temperature yield strength and creep-rupture life are needed, at the cost of ductility and toughness. | 560 | 930 | 25 | 24 HRC | — |
Cold drawn | Cold-drawn bar and wire for fasteners and small machined parts needing higher strength, straightness and surface finish. | 760 | 1,000 | 20 | 30 HRC | 1.9 % IACS |
CR 1/2-Hard | Cold-rolled strip where springback-tolerant higher strength is needed in thin sheet parts (clamps, seals, shims). | 900 | 1,100 | 12 | 34 HRC | 1.9 % IACS |
What is N-155 (Multimet)-SA?
N-155 (Multimet)-SA is N-155 (Multimet) heat treated to SA — standard stocked condition for sheet, plate, bar and forgings; best ductility and formability, and the condition from which parts are welded and formed. N-155 (Multimet)-SA has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 62% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi). N-155 (Multimet)-SA has a density of 8.19 g/cm³ (0.296 lb/in³), heavier than 100% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Advantages
- High service temperature — 815°C (1,499 °F), better than 77% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- High embodied carbon — 8 kg CO₂/kg, worse than 99% of stainless steel grades
- Difficult to machine — 20/100, worse than 98% of stainless steel grades
- Poor heat conductor — 12.3 W/m·K (7.11 BTU/hr·ft·°F), worse than 91% of stainless steel grades
- Low electrical conductivity — 1.9 % IACS, worse than 84% of stainless steel grades
N-155 (Multimet)-SA properties
Typical room-temperature values for N-155 (Multimet)-SA; 12 are specific to this condition. Other listed values are N-155 (Multimet) reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
N-155 (Multimet)-SA has a density of 8.19 g/cm³ (0.296 lb/in³), heavier than 100% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Mechanical14
N-155 (Multimet)-SA has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 62% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
N-155 (Multimet)-SA is rated for continuous service to 815°C (1,499 °F). It conducts heat at 12.3 W/m·K (7.11 BTU/hr·ft·°F), worse than 91% of stainless steel grades. Thermal expansion is 14.4 µm/m·K (8 µin/in·°F).
Electrical3
N-155 (Multimet)-SA conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.
Chemical & Environmental2
Corrosion resistance is good (68/100), better than 63% of stainless steel grades.
Sustainability4
Producing a kilogram of N-155 (Multimet)-SA takes about 95 MJ of energy and emits 8 kg of CO₂ — more than 96% of stainless steel grades. Typical recycled content is 35%.
Manufacturability7
N-155 (Multimet)-SA's machinability is poor (20/100, worse than 98% of stainless steel grades); weldability very good (70/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with N-155 (Multimet)-SA
Is N-155 (Multimet) easy to machine?
Machine like a solid-solution superalloy: rigid setups, positive-rake carbide or ceramic tooling, low speed / heavy positive feed to cut under the work-hardened layer, flood coolant; avoid dwelling and rubbing.
Can N-155 (Multimet) be welded?
Readily GTAW/GMAW/EBW welded with matching N-155 or Ni-base (e.g. ERNiCrMo) filler, low heat input and no preheat; solution anneal after welding if maximum ductility or creep life is required.
Can N-155 (Multimet) be formed, bent or molded?
Formable in the solution-annealed condition but work-hardens rapidly — allow generous bend radii, use intermediate anneals for severe draws, or hot form at 1000–1180 °C.
What surface finishes work on N-155 (Multimet)?
Not anodizable; passivate or pickle after heat treatment to remove oxide, and use aluminizing or diffusion/TBC coatings for extended service above ~900 °C.
N-155 (Multimet) 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 | 0.08 – 0.16 | 0.12 |
| Mn | 1 – 2 | 1.5 |
| Si | ≤ 1 | 0.5 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 20 – 22.5 | 21 |
| Ni | 19 – 21 | 20 |
| Co | 18.5 – 21 | 20 |
| Mo | 2.5 – 3.5 | 3 |
| W | 2 – 3 | 2.5 |
| Nb+Tacolumbium plus tantalum | 0.75 – 1.25 | 1 |
| Nsolid-solution and nitride strengthener | 0.1 – 0.2 | 0.15 |
| Febalance, approx. 30 % | balance | — |
N-155 (Multimet)-SA — frequently asked
What is N-155 (Multimet)-SA used for?
N-155 (Multimet)-SA is typically used for gas turbine combustors and afterburner parts, jet engine exhaust components, high-temperature fasteners and aerospace superheater hardware. In short: superalloy-class austenitic; highest strength in family; gas-turbine hot-section sheet.
What is the yield strength of N-155 (Multimet)-SA?
N-155 (Multimet)-SA has a typical yield strength of 415 MPa (60.2 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 62% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is N-155 (Multimet)-SA easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of stainless steel grades). Machine like a solid-solution superalloy: rigid setups, positive-rake carbide or ceramic tooling, low speed / heavy positive feed to cut under the work-hardened layer, flood coolant; avoid dwelling and rubbing.
Can N-155 (Multimet)-SA be welded?
Yes — weldability is rated very good (70/100). Readily GTAW/GMAW/EBW welded with matching N-155 or Ni-base (e.g. ERNiCrMo) filler, low heat input and no preheat; solution anneal after welding if maximum ductility or creep life is required.
What surface finishes work on N-155 (Multimet)-SA?
Not anodizable; passivate or pickle after heat treatment to remove oxide, and use aluminizing or diffusion/TBC coatings for extended service above ~900 °C.
Can N-155 (Multimet)-SA be formed, bent or molded?
Formable in the solution-annealed condition but work-hardens rapidly — allow generous bend radii, use intermediate anneals for severe draws, or hot form at 1000–1180 °C.
What is the maximum service temperature of N-155 (Multimet)-SA?
N-155 (Multimet)-SA is rated for continuous use to about 815°C (1,499 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between N-155 (Multimet)-SA and N-155 (Multimet)-CD?
SA is the default condition — standard stocked condition for sheet, plate, bar and forgings; best ductility and formability, and the condition from which parts are welded and formed. CD: cold-drawn bar and wire for fasteners and small machined parts needing higher strength, straightness and surface finish. Yield strength is 415 MPa in SA versus 760 MPa in CD.
Sources
- AMS 5532 — Alloy Sheet, Strip and Plate, 21Cr-20Ni-20Co-3Mo-2.5W-1Cb — SAE International (2018)
- AMS 5768 — Alloy Bars, Forgings and Rings (N-155) — SAE International (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (heat-resistant alloys) — ASM International (1990)
- ASM Handbook Vol.16 — Machining (heat-resistant alloys) — ASM International (1989)
- UNS R30155 alloy data — SAE/ASTM Unified Numbering System (2020)
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.