Nickel Alloy ENiMo-7
UNS W80665
ENiMo-7 (W80665) is a covered nickel-molybdenum electrode from the AWS A5.11 filler family, the shielded metal arc version of the B-2 filler system for joining and repairing Ni-Mo alloys and for overlay in hydrochloric acid service.
Reference datasheet — ENiMo-7 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 AW condition
ENiMo-7 tempers and conditions
ENiMo-7 is supplied in 3 conditions, soft to hard. AW 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 |
|---|---|---|---|---|---|---|
Post-weld solution annealed 1065–1120 °C, rapid quench | Choose when the fabrication can be furnace-treated: dissolves interdendritic Mo-rich segregation and restores maximum HCl corrosion resistance and ductility. | 400 | 780 | 42 | 205 HB | 1.3 % IACS |
Stress relieved | Low-temperature relief for distortion/residual-stress control only; must stay clear of the 550–800 °C ordering range that embrittles Ni-Mo weld metal. | 455 | 810 | 34 | 19 HRC | 1.3 % IACS |
AWDefault As-welded deposit | Standard condition for field repair and site welding of B-2 equipment where no post-weld heat treatment is possible. | 470 | 820 | 33 | 20 HRC | 1.3 % IACS |
What is ENiMo-7?
ENiMo-7 (W80665) is a covered nickel-molybdenum electrode from the AWS A5.11 filler family, the shielded metal arc version of the B-2 filler system for joining and repairing Ni-Mo alloys and for overlay in hydrochloric acid service. Deposited all-weld metal runs about 470 MPa yield, 820 MPa tensile and 33 % elongation at 230 HB (98 HRB), with a corrosion rating of 80 and service to 425 °C. The deposit work-hardens severely, so machinability is low (score 18) and dressing by grinding is usually faster than cutting. Where torch access allows, the bare-wire ERNiMo-7 equivalent for GTAW gives cleaner, slag-free deposits. ENiMo-7 has a density of 9.22 g/cm³ (0.333 lb/in³), heavier than 97% of nickel alloy grades. It melts at 1,330°C (2,426 °F). ENiMo-7 has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 68% of nickel alloy grades. Elongation at break is 33% and the elastic modulus is 217 GPa (31.5 Msi).
What is ENiMo-7 used for?
- Field repair of HCl service vessels
- Manual welding of Ni-Mo alloy (B-2 type) components
- Weld overlay on steel for reducing-acid duty
- Repair of nickel alloy pump and valve castings
- On-site pipe spool welds in acid plants
- Patch welds on reactors and digesters
Limitations
- Low electrical conductivity — 1.3 % IACS, worse than 97% of nickel alloy grades
- Limited service temperature — 425°C (797 °F), worse than 90% of nickel alloy grades
ENiMo-7 properties
Typical room-temperature values for ENiMo-7-AW; bars are the position among nickel alloy grades.
Physical3
ENiMo-7 has a density of 9.22 g/cm³ (0.333 lb/in³), heavier than 97% of nickel alloy grades. It melts at 1,330°C (2,426 °F).
Mechanical17
ENiMo-7 has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 68% of nickel alloy grades. Elongation at break is 33% and the elastic modulus is 217 GPa (31.5 Msi).
Thermal5
ENiMo-7 is rated for continuous service to 425°C (797 °F). It conducts heat at 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 60% of nickel alloy grades. Thermal expansion is 10.3 µm/m·K (5.72 µin/in·°F).
Electrical3
ENiMo-7 conducts electricity at 1.3 % IACS, worse than 97% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (80/100), better than 61% of nickel alloy grades.
Sustainability4
Producing a kilogram of ENiMo-7 takes about 175 MJ of energy and emits 13.5 kg of CO₂ — more than 65% of nickel alloy grades. Typical recycled content is 30%.
Manufacturability6
ENiMo-7's machinability is poor (18/100, worse than 61% of nickel alloy grades); weldability very good (70/100); formability fair (45/100).
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. ENiMo-7 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ENiMo-7
Is ENiMo-7 easy to machine?
Weld metal work-hardens severely — use sharp carbide, heavy positive rake, slow speed with high feed and flood coolant; grind rather than machine where possible.
Can ENiMo-7 be welded?
DCEP, stringer beads, low heat input (<1.5 kJ/mm), interpass below 100–120 °C, electrodes rebaked at ~250–300 °C to avoid porosity; keep joints free of iron and copper contamination.
Can ENiMo-7 be formed, bent or molded?
Not a forming product; deposit is ductile enough for light peening/dressing but avoid heavy cold work before service in acid.
ENiMo-7 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 |
|---|---|---|
| Mo | 26 – 30 | 28 |
| Fe | ≤ 2 | 1 |
| Cr | ≤ 1 | 0.5 |
| Co | ≤ 1 | |
| W | ≤ 1 | |
| Mn | ≤ 1.75 | 0.8 |
| Si | ≤ 0.2 | 0.08 |
| C | ≤ 0.02 | 0.01 |
| Cu | ≤ 0.5 | |
| P | ≤ 0.04 | |
| S | ≤ 0.03 | |
| Other, total | ≤ 0.5 | |
| Niremainder, typically ~68–70 % | balance |
What surface finishes work on ENiMo-7?
Grind flush and pickle/passivate lightly or mechanically clean to remove slag, oxide and any embedded iron before commissioning in HCl service.
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 ENiMo-7 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- W80665
How much does ENiMo-7 cost?
ENiMo-7 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.
ENiMo-7 — frequently asked
What is ENiMo-7 used for?
ENiMo-7 is typically used for field repair of HCl service vessels, manual welding of Ni-Mo alloy (B-2 type) components, weld overlay on steel for reducing-acid duty, repair of nickel alloy pump and valve castings, on-site pipe spool welds in acid plants and patch welds on reactors and digesters. In short: manual electrode for B-2; reducing-acid weld metal; field-repair Ni-Mo filler.
What is the yield strength of ENiMo-7?
ENiMo-7 has a typical yield strength of 470 MPa (68.2 ksi) and a tensile strength of 820 MPa (119 ksi) — stronger than 68% of nickel alloy grades. Strength varies by condition: see the 3 listed tempers.
Is ENiMo-7 easy to machine?
Not especially — machinability is rated poor (18/100, worse than 61% of nickel alloy grades). Weld metal work-hardens severely — use sharp carbide, heavy positive rake, slow speed with high feed and flood coolant; grind rather than machine where possible.
Can ENiMo-7 be welded?
Yes — weldability is rated very good (70/100). DCEP, stringer beads, low heat input (<1.5 kJ/mm), interpass below 100–120 °C, electrodes rebaked at ~250–300 °C to avoid porosity; keep joints free of iron and copper contamination.
What surface finishes work on ENiMo-7?
Grind flush and pickle/passivate lightly or mechanically clean to remove slag, oxide and any embedded iron before commissioning in HCl service.
Can ENiMo-7 be formed, bent or molded?
Not a forming product; deposit is ductile enough for light peening/dressing but avoid heavy cold work before service in acid.
What is the maximum service temperature of ENiMo-7?
ENiMo-7 is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ENiMo-7-AW and ENiMo-7-SA?
AW is the default condition — standard condition for field repair and site welding of B-2 equipment where no post-weld heat treatment is possible. SA: choose when the fabrication can be furnace-treated: dissolves interdendritic Mo-rich segregation and restores maximum HCl corrosion resistance and ductility. Yield strength is 470 MPa in AW versus 400 MPa in SA.
How much does ENiMo-7 cost?
ENiMo-7 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
- AWS A5.11/A5.11M — Nickel and Nickel-Alloy Welding Electrodes for Shielded Metal Arc Welding — American Welding Society (2018)
- ASTM B333 / UNS N10665 (alloy B-2) plate and sheet — ASTM International (2018)
- Nickel-molybdenum alloy B-2 physical and corrosion data — Haynes International / Special Metals (2020)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Ni alloys) — ASM International (1993)
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.