Nimonic Alloy 105 is a precipitation-strengthened nickel-cobalt-chromium superalloy engineered for sustained high-temperature strength and creep resistance up to roughly 950°C (≈1740°F); it is widely used for turbine blades, discs, hot-section forgings and high-temperature fasteners where long-term dimensional stability and oxidation resistance are essential.

• Family: Nickel-base, precipitation-strengthened superalloy (nickel-cobalt-chromium base).

• Werkstoff / W. Nr.: 2.4634 (often listed as Nimonic 105).

• Service temperature: designed for sustained use up to ≈950°C; excellent creep-resistance in that range.

• Typical uses: turbine blades and discs, high-temperature fasteners, hot-section forgings, rings and critical components in gas turbines and industrial high-temperature equipment.

What is Nimonic 105?

Nimonic 105 is a wrought nickel-cobalt-chromium superalloy developed in the mid-20th century as part of the Nimonic family of heat-resistant alloys. It combines a nickel-rich matrix with controlled amounts of cobalt and chromium for corrosion/oxidation resistance, while molybdenum, aluminium and titanium produce both solid-solution and precipitation strengthening (the latter after ageing). The microstructure and chemistry were chosen to give high tensile and creep strength at temperatures encountered in aero-engine and industrial gas-turbine hot sections. These properties make it a workhorse for components that must retain strength and resist deformation for thousands of hours at high temperature.

Chemical composition

Below is a concise table built from manufacturer technical data (typical composition ranges used for specification). Use the exact spec on purchase orders — small changes in carbon, Al or Ti have measurable effects on precipitation behaviour.

(Source: Special Metals technical bulletin for NIMONIC® alloy 105; composition table condensed.)

Note: suppliers and national standards sometimes show slightly different upper/lower limits; always quote the spec referenced in your drawing (e.g., BS HR3 / W. Nr. 2.4634).

Key physical & mechanical properties

The following table summarizes the commonly cited physical and mechanical numbers. Values depend strongly on heat treatment, product form (bar, extruded section, forged), and test temperature.

Engineering note: single numeric values can be misleading for superalloys: pick property tables from the supplier that match the heat treatment and product form you intend to use. Special Metals publishes detailed tensile, creep and fatigue curves that engineers rely on when sizing parts.

Standards and equivalents

Nimonic 105 is referred to in various national/industry systems. Common designations and cross-references include:

• Werkstoff / W. Nr.: 2.4634.

• British / European: BS HR3 (and related HR designations).

• Other listings: AFNOR NCKD 20ATv; commonly shown in aerospace alloy lists as “Alloy 105 / Nimonic 105”.

Equivalents: because composition and heat-treatment philosophies vary, there is no perfect one-to-one substitute; however, in many procurement contexts Nimonic 105 corresponds to DIN 2.4634 and to older alloy naming schemes used in aero and industrial catalogs. Always confirm the required composition and mechanical spec rather than relying solely on a trade name.

What is Nimonic 105 used for?

Typical uses—driven by its strength, creep resistance and oxidation resistance—include:

• Aerospace & industrial gas turbine components: blades, vanes, discs, rings and combustor parts that operate in hot sections.

• High-temperature fasteners and bolts: where long-term preload retention at elevated temperature is required.

• Hot-work tooling and forging dies that require heat resistance and dimensional stability.

• Specialty springs and retention parts in environments that see cyclic heating and high stress.

Why engineers choose it: the alloy offers a blend of age-hardenable matrix (Al + Ti precipitates) and solid-solution strengthening (Mo, Co) that yields high tensile and creep performance without the casting-only limitations of some single-crystal or directionally solidified superalloys. This makes Nimonic 105 attractive for wrought components and forgings that must be machined and heat-treated to tight tolerances.

Heat treatment, fabrication and joining

Heat treatments (manufacturer recommendations): the Special Metals bulletin gives two frequently used regimes tailored to component type:

• Treatment A (optimum long-term creep strength): 4 h / 1150°C air cool + 16 h / 1050–1065°C air cool + 16 h / 850°C air cool.

• Treatment B (for higher tensile strength & improved RT properties when long-term creep is less critical): 4 h / 1125°C AC + 16 h / 850°C AC.
  Use treatment (A) for turbine blades/discs; (B) when demanding creep life is not central.

Hot working: recommended range ~1050–1200°C; interstage anneals at ~1150°C if heavy deformation is performed.

Machining: machine in fully heat-treated condition where possible; hardness dictates carbide tooling (tungsten carbide tips), low feed/high rigidity practices.

Welding: fusion welding (TIG/MIG) can be problematic due to microfissuring in weld and HAZ; electron-beam and flash-butt welding have been used successfully in production, but qualification tests are mandatory. High-temperature brazing in vacuum/dry hydrogen/inert atmospheres is a common joining method when temperatures stay below the solution treatment.

Practical tip: specify permitted heat treatments, required post-weld heat treatment (if any), and NDT qualification in purchase orders — components using Nimonic 105 are often safety-critical.

Size, shapes and weight

Nimonic 105 is produced by specialty mills and service centers in many product forms. Typical commercial items include bars, billets, extruded sections, sheet/plate (thin sheet & thicker plate), tubes and forgings.

Representative size & weight table

Weight example: a 1000 mm length of Ø50 mm round bar weighs ≈ π·(0.05²/4)·1 m ·8.01 g/cm³ → ≈15.7 kg (engineer should compute exact mass from geometry). (Use density 8.01 g/cm³ for conversions.)

Global 2025 price comparison

Market note: prices for specialty nickel superalloys depend strongly on form (bar vs plate vs finished fastener), quantity, mill lead time, and raw-material surcharge. The following ranges are approximate market indicators gathered from current supplier price sheets and marketplace listings (FOB or listed supplier price per kg). Use them only for budgeting — get formal quotes for procurement.

Sources & caveats: these ranges combine marketplace listings (Made-in-China, factory FOB pages), specialty alloy distributors and alloy surcharge indexes; price can swing with nickel/cobalt markets, form, certification required and order volume. For precision budgeting, request mill quotes that reference the full specification (BS HR3 / W. Nr. 2.4634) and heat treatment.

Supply, lead time and why buy Nimonic 105 from MWalloys

MWalloys — about us (short): MWalloys is a specialty metal supplier and processor focused on high-temperature nickel-base materials for industrial and aerospace sectors. We maintain factory relationships and stock common Nimonic grades to supply forged rings, bar, plate and cut-to-length items.

What MWalloys offers for Nimonic 105:

• 100% factory price on many standard forms (we buy direct from mills and pass savings to our customers).

• Fast stock delivery for typical bar, plate and sheet sizes — inventory enables short lead times for many orders.

• Certificates & traceability: material test reports (MTRs), heat-number traceability, and test records supplied with each shipment.

• Manufacturing support: machining, forging partnering and pre-qualified heat treatments on request.

If you need a formal quote, include: required standard (e.g., BS HR3 / W. Nr. 2.4634), product form, dimensions, heat-treatment/temper requirement, quantity and delivery port — MWalloys will respond with mill-direct pricing and estimated ready-to-ship times.

Practical purchasing tip: for critical rotating or safety components, require certified mill-or-facility traceability and any necessary third-party testing (e.g., PMI/chemical check, NDT) in the purchase order.

How to specify Nimonic 105 in procurement

When writing technical purchase documents, include:

1. Exact alloy designation (e.g., Nimonic Alloy 105, W. Nr. 2.4634, BS HR3).

2. Required material form (bar, plate, extruded section, forging blank).

3. Chemical composition tolerance or reference spec. (quote the BS/EN version or Special Metals data sheet).

4. Heat treatment (specify which of the manufacturer’s suggested regimes or an agreed alternative).

5. Mechanical property acceptance criteria (tensile, yield, elongation at RT and where needed at elevated temperatures).

6. Non-destructive testing & acceptance (if required e.g., ultrasonic on forgings, PMI).

7. Documentation (MTR per EN 10204 3.1/3.2 or equivalent).

8. Special processes (welding/brazing instructions, machining allowances, post-weld heat treat).

9. Quantity and delivery schedule — tie to supplier confirmation and lead time.

10. Commercial terms — FOB/CIF, incoterms, payment and warranty.

FAQs

1. Is Nimonic 105 the same as Inconel 625 or 718?
No. Nimonic 105 belongs to the Nimonic family (nickel-cobalt-chromium with Al/Ti precipitation strengthening). Inconel 625 and 718 are different nickel-base alloys with different alloying balances and performance envelopes; do not substitute without engineering review.

2. What temperature can it operate at continuously?
It is engineered for sustained service up to ≈950°C, with specific component life depending on stress, environment and heat treatment. Use the manufacturer’s creep-rupture curves to size parts.

3. What is the standard heat treatment?
Two common regimens are published: the long-life cycle (4 h @ 1150°C AC → 16 h @ 1050–1065°C AC → 16 h @ 850°C AC) for creep life, and a shorter solution + ageing (4 h @ 1125°C AC → 16 h @ 850°C AC) for higher RT strength where creep life is less critical. Specify which you require.

4. Can Nimonic 105 be welded?
Fusion welding is challenging and can produce microfissures; electron beam welding and flash-butt have seen success. Brazing in controlled atmospheres is commonly used. Welding must be qualified on the specific component and assembly.

5. Does Nimonic 105 require special machining tooling?
Yes — because of high hardness after heat-treatment, carbide tooling and careful process design (rigidity, conservative feeds) are recommended. Machine in the final heat-treated condition where possible.

6. What are common forms available from mills?
Round bar, extruded sections, plate & sheet, tube, forged blanks and ring forgings. Availability depends on mill and minimum order quantities.

7. How does carbon content affect properties?
Nimonic 105 has a relatively high upper carbon limit (0.17 wt% max). Carbon influences carbide formation and thus creep and fabricability; recent studies examine carbon’s effect on creep and microstructure stability.

8. Is it corrosion resistant?
It has good high-temperature oxidation resistance due to Cr and Al but is not a general corrosion-resistant alloy for aggressive aqueous chemistries—select a corrosion-rated alloy if that is the primary requirement.

9. What documentation should I insist on?
Mill MTR (chemical & mechanical), heat-treatment record, and any required NDT reports. For aerospace or safety-critical use, a higher degree of certification and traceability (3.1/3.2 or similar) is common.

10. How do I get a reliable price and lead time?
Provide exact spec (W. Nr./BS or AMS if applicable), form, dimensions, quantity and desired treatments to suppliers. Large orders reduce per-kg costs; MWalloys can provide mill quotes and typically holds stock for faster dispatch on common sizes.