MOLYBDENUM–TUNGSTEN ALLOY MILL PRODUCTS & PARTS
Mo30W Molybdenum–Tungsten Alloy
Technical sourcing for ASTM Grade 366 and manufacturer-controlled MoW mill products and components.
MNK-G.S.A sources molybdenum–tungsten material by exact composition, production route, product form, dimensions, condition, inspection documents and destination. Mo30W is kept separate from pure molybdenum, TZM and tungsten–copper composites.
Mo30W Is a Defined Alloy Route
ASTM identifies Alloy 366 as vacuum arc-cast Mo with 30 % W. The designation MoW alone does not establish conformity. Plansee lists MoW30 with nominal 30 wt.% W; this manufacturer designation is not by itself an ASTM certificate.
Material Definition and Supply Scope
ASTM Grade 366
Vacuum arc-cast molybdenum–30 % tungsten alloy within the applicable flat- or long-product scope of ASTM B386/B386M and B387/B387M.
Rod and Bar
Forged, extruded, rolled or machined long products sourced by Grade 366 or an agreed manufacturer composition, diameter, length, finish and tolerances.
Sheet, Plate and Foil
Flat products sourced by chemistry, route, thickness, width, length, rolling condition, surface and inspection requirements.
Heating Elements
MoW heating-element and furnace-part inquiries require operating temperature, atmosphere, geometry, electrical loading and joint details.
Custom Components
Machined and fabricated parts are reviewed against drawing, starting form, grain direction, tolerances and inspection plan.
Other MoW Ratios
A commercial MoW designation with a different tungsten content is treated as a separate manufacturer grade and is not called ASTM Grade 366 without evidence.
Supply Forms and Size Confirmation
Dimensions are agreed for the specified composition, product form and production route. The manufacturer examples below are reference capabilities, not MNK stock or a universal MoW size range.
| Product Form | Sizing basis | Notes |
|---|---|---|
| Rod / Bar | By composition and specification | See the separately identified Mo30W manufacturer example below. |
| Sheet / Plate / Foil | According to specification | Thickness and format depend on composition, production route and condition. |
| Blanks / Custom Parts | According to drawing | Starting stock and machining feasibility are reviewed individually. |
A size demonstrated for Mo30W is not automatically guaranteed for another Mo/W composition.
Actual availability depends on grade, specification, quantity, tolerances, certification requirements and manufacturing source. Diameter, thickness, width and length must be confirmed as one complete combination.
Composition-Specific Mo–W Product Examples
Mo30W bar and manufacturer-designated MB wire are separate production programmes. Their dimensional limits cannot be combined or transferred to another molybdenum–tungsten ratio.
| Material / form | Published range | Qualification |
|---|---|---|
| Mo30W bar / rod | Ø0.125–3.25 in (Ø3.175–82.55 mm) | Elmet: Mo30W bar / rod. Confirm production route, condition and the complete diameter/length combination for the order. |
| MB Mo–W special-oxidised wire | Below Ø0.0254 mm to Ø0.0762 mm | Elmet MB wire: source range <0.001 in to 0.003 in. Confirm composition, resistance and finish. |
| MB Mo–W cleaned wire | Ø0.0762–0.762 mm | Elmet MB wire: source range 0.003–0.03 in. MB does not establish ASTM Alloy 366 conformity. |
| Flat products and custom parts | According to governing composition and specification | Wire or bar dimensions do not establish sheet, plate, foil or machined-part capability. |
For each inquiry, MNK-G.S.A confirms the Mo/W mass fraction, ASTM grade where requested, melting or powder-metallurgy route, dimensions, condition, finish, required properties and inspection documents. A commercial family name is not accepted as proof of standard compliance.
Standards and Documentation
ASTM B386/B386M-25
Flat-product scope includes Alloy 366 plate, sheet, strip, foil and ribbon. Official scope: §1.1.6.
ASTM B387/B387M-23
Alloy 366 bar, rod and wire: minimum wire boundary ≥0.02 in or ≥0.51 mm. Use each unit system independently; finer wire is not automatically covered. Public scope §§1.1.6, 1.2 and 1.3.
Grade Verification
Grade 366 identity requires documented chemistry and production route. “MoW” alone is not sufficient evidence of ASTM conformity.
EN 10204:2004
European inspection-document type may be specified together with chemistry, mechanical, dimensional and traceability requirements supported by the selected source.
EN / DIN Requirements
No EN or DIN grade is assumed equivalent to ASTM Grade 366. Any requested European or national standard is reviewed by exact document number and scope.
Application Documents
Critical parts may require drawing revision control, inspection report, material certificate, additional testing and agreed traceability.
Application Context
High-Temperature Furnaces
Heating elements, shields, supports and fabricated furnace parts where MoW is specified for the service environment.
Thermal Processing
Components for sintering, heat treatment and other high-temperature equipment after atmosphere and load review.
Custom Engineering
Machined and fabricated parts developed from verified Grade 366 or an agreed manufacturer MoW specification.
Capability Note
Published dimensional ranges describe demonstrated manufacturing capability across specialist sources, not guaranteed stock and not one universal mill envelope. Diameter, thickness, width, length, condition, tolerance and quantity must be confirmed as one complete combination for each inquiry.
Technical Sources and Revision
Technical review: 14 September 2026. Manufacturer web pages are undated; the date here records our review, not a new manufacturer edition.
The diameter examples were checked against the two Elmet web sources on 15 October 2026. Both inch and millimetre displays now come from the same shared registry facts. Decimal inches are equivalent to the fractions in the source; the below-threshold qualification and all scope limitations are retained. This review does not renew other sources on this page.
- Plansee: molybdenum alloys: MoW section and alloy table; nominal composition.
- Elmet: bar and rod: Molybdenum specification section; Mo30W diameter example.
- Elmet: wire products: MB wire table; diameter and surface condition.
- ASTM B386/B386M-25: Public scope §1.1.6; flat products.
- ASTM B387/B387M-23: Public scope §§1.1.6 and 1.2; long products and wire limit.
External documents are in English. Inch-to-millimetre values in the manufacturer examples are reference conversions (1 in = 25.4 mm), not new tolerances or a replacement for the governing specification. References do not establish stock, a supplier relationship or conformity of a particular lot; these require order-specific confirmation.
Send Your Mo30W Molybdenum–Tungsten Alloy Inquiry
Provide the material grade or composition, governing specification, product form, complete dimensions, quantity, inspection-document requirements and delivery destination.
Sources and scope checked
Source review date:
Review limits: Review limited to the listed product forms and production routes. Separate standard scopes from manufacturer examples; numerical properties and MNK availability are not certified by this review.
- ASTM B386/B386M-25
Alloy 366 flat products made by the specified vacuum arc-cast route. Public scope 1.1.6; nominal composition is maintained in the shared registry.
- ASTM B387/B387M-23
Alloy 366 vacuum arc-cast bar, rod and wire. Public scope 1.1.6, 1.2 and 1.3: separate SI/inch minimum wire boundaries in the shared registry; no PM conformity implied.
- POLEMA: MoW30-PM crucibles and furnace components
Specifications sections 3-4: MoW30-PM crucibles and furnace components made by powder metallurgy. Geometry and condition are agreed by drawing; no ASTM Alloy 366 conformity is established.
- Plansee: MoW30 nominal composition, brochure p.6
Manufacturer composition by mass, not a batch analysis or ASTM Alloy 366 certificate. The numeric value is maintained in the shared registry; brochure revision not established.