Refractory Metal Mo-30W
ASTM B387 Grade 365 · GB MoW30
Mo-30W (UNS R03630, MoW30, ASTM B387 Grade 365) is a powder-metallurgy solid-solution molybdenum-tungsten alloy supplied stress-relieved, cold-worked, recrystallised, as-sintered, hot-forged or as-cast.
Reference datasheet — Mo-30W 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 SR condition
Mo-30W tempers and conditions
Mo-30W is supplied in 6 conditions, soft to hard. SR is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PM-Sintered | Pick for large near-net blanks, crucibles, nozzles and sputter-target backing where residual porosity (typically 95–98 % of theoretical density) is acceptable. | 330 | 430 | 5 | 15 HRC | 11.9 % IACS |
Recrystallized / fully annealed | Use where dimensional stability after long high-temperature service matters (glass-contact hardware, furnace parts); softest and lowest strength, and the most brittle at room temperature. | 420 | 560 | 25 | 95 HRB | — |
hot worked / forged (thick bar, billet, rings) | Heavy sections and forged shapes (zinc pump bodies, stirrer shafts) where full wrought density and moderate strength are needed but heavy cold work is impossible. | 540 | 690 | 20 | 20 HRC | 13 % IACS |
Spheroidize annealed | Specify when very low interstitial (C, O, N) content and freedom from powder-route porosity are required, e.g. electrodes and glass-contact parts with long service life. | 580 | 720 | 22 | 21 HRC | 13 % IACS |
SRDefault Stress relieved | Standard commercial condition for rod, plate and machined parts: worked fibre structure retained, internal stresses removed, best balance of strength and workability. | 620 | 760 | 18 | 23 HRC | 100 W/m·K |
Cold worked | Choose for maximum room-temperature strength and stiffness in thin sheet, foil, wire and electrodes where no high-temperature exposure will recrystallize the part. | 950 | 1,050 | 7 | 33 HRC | — |
What is Mo-30W?
Mo-30W (UNS R03630, MoW30, ASTM B387 Grade 365) is a powder-metallurgy solid-solution molybdenum-tungsten alloy supplied stress-relieved, cold-worked, recrystallised, as-sintered, hot-forged or as-cast. Engineers select it because it resists molten zinc and molten glass better than pure molybdenum while being stronger: 620 MPa yield, 760 MPa tensile, 18% elongation, 23 HRC and 100 W/m·K. Limits are poor weldability (score 20), low room-temperature ductility and formability (25), rapid oxidation in air above roughly 600 °C and a 500 °C bare-air service ceiling. TZM is the alternative when high-temperature structural strength matters more than molten-metal corrosion. Mo-30W has a density of 11.9 g/cm³ (0.43 lb/in³), heavier than 73% of refractory metal grades. It melts at 2,740°C (4,964 °F). Mo-30W has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 84% of refractory metal grades. Elongation at break is 18% and the elastic modulus is 340 GPa (49.3 Msi).
What is Mo-30W used for?
- Molten zinc pump/pipe components
- Glass furnace stirrers
- Zinc galvanizing hardware
- Corrosion-resistant fixtures
Advantages
- Stiff — 340 GPa (49.3 Msi), better than 89% of refractory metal grades
- Low embodied carbon — 13 kg CO₂/kg, better than 87% of refractory metal grades
- High strength — 620 MPa (89.9 ksi), better than 84% of refractory metal grades
- Conducts heat well — 100 W/m·K (57.8 BTU/hr·ft·°F), better than 76% of refractory metal grades
Limitations
- Difficult to weld — 20/100, worse than 79% of refractory metal grades
- Low fracture toughness — 15 MPa·√m (13.7 ksi·√in), worse than 75% of refractory metal grades
Mo-30W properties
Typical room-temperature values for Mo-30W-SR; bars are the position among refractory metal grades.
Physical3
Mo-30W has a density of 11.9 g/cm³ (0.43 lb/in³), heavier than 73% of refractory metal grades. It melts at 2,740°C (4,964 °F).
Mechanical15
Mo-30W has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 84% of refractory metal grades. Elongation at break is 18% and the elastic modulus is 340 GPa (49.3 Msi).
Thermal6
Mo-30W is rated for continuous service to 500°C (932 °F). It conducts heat at 100 W/m·K (57.8 BTU/hr·ft·°F), better than 76% of refractory metal grades. Thermal expansion is 5 µm/m·K (2.78 µin/in·°F).
Electrical3
Mo-30W conducts electricity at 13 % IACS, better than 71% of refractory metal grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 72% of refractory metal grades.
Sustainability4
Producing a kilogram of Mo-30W takes about 205 MJ of energy and emits 13 kg of CO₂ — less than 86% of refractory metal grades. Typical recycled content is 20%.
Manufacturability8
Mo-30W's machinability is poor (30/100, better than 54% of refractory metal grades); weldability poor (20/100); formability poor (25/100).
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 refractory metal family
Yield strength against density for every refractory metal grade FabDigit runs. Mo-30W is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Mo-30W
Is Mo-30W easy to machine?
Machine with sharp, positive-rake carbide or CBN tooling, rigid setups, generous flood coolant and light finishing passes; the alloy is abrasive and notch-sensitive, and warming stock to 100–200 °C reduces chipping in drilling/tapping.
Can Mo-30W be welded?
Fusion welding (EB, laser, GTAW in high-purity argon or vacuum) is possible but the weld and HAZ recrystallize and become brittle at RT; vacuum brazing or mechanical joining is preferred for service parts.
Can Mo-30W be formed, bent or molded?
Bend, deep-draw or spin only warm (typically 200–500 °C, above the DBTT) with generous radii; cold forming of recrystallized material cracks readily.
Mo-30W 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 |
|---|---|---|
| Wsolid-solution alloying addition | 28.5 – 31.5 | 30 |
| Cimpurity limit | ≤ 0.01 | 0.01 |
| Oimpurity limit, powder route | ≤ 0.01 | 0 |
| Nimpurity limit | ≤ 0 | 0 |
| Feimpurity limit | ≤ 0.01 | 0 |
| Niimpurity limit | ≤ 0.01 | 0 |
| Siimpurity limit | ≤ 0.01 | 0 |
| Mobalance, ≥ 68 % typical | balance |
What surface finishes work on Mo-30W?
Grind/lap or electropolish for smooth surfaces; for use above ~600 °C in air apply silicide (MoSi₂) or Si-Cr-Fe diffusion coatings, and Ni or Cr plating for aqueous/wetting control in zinc-bath hardware.
Equivalent designations
Standards and trade names that resolve to Refractory Metal Mo-30W in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B387 Grade 365
- GB (China)
- MoW30
- Similar grades
- R03630B387
How much does Mo-30W cost?
Mo-30W is a high-cost refractory metal ($$$$), 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.
Mo-30W — frequently asked
What is Mo-30W used for?
Mo-30W is typically used for molten zinc pump/pipe components, glass furnace stirrers, zinc galvanizing hardware and corrosion-resistant fixtures. In short: molten-zinc resistant moly; stronger than pure molybdenum; glass-contact refractory metal.
What is the yield strength of Mo-30W?
Mo-30W has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 84% of refractory metal grades. Strength varies by condition: see the 6 listed tempers.
Is Mo-30W easy to machine?
Not especially — machinability is rated poor (30/100, better than 54% of refractory metal grades). Machine with sharp, positive-rake carbide or CBN tooling, rigid setups, generous flood coolant and light finishing passes; the alloy is abrasive and notch-sensitive, and warming stock to 100–200 °C reduces chipping in drilling/tapping.
Can Mo-30W be welded?
Not readily — weldability is rated poor (20/100). Fusion welding (EB, laser, GTAW in high-purity argon or vacuum) is possible but the weld and HAZ recrystallize and become brittle at RT; vacuum brazing or mechanical joining is preferred for service parts.
What surface finishes work on Mo-30W?
Grind/lap or electropolish for smooth surfaces; for use above ~600 °C in air apply silicide (MoSi₂) or Si-Cr-Fe diffusion coatings, and Ni or Cr plating for aqueous/wetting control in zinc-bath hardware.
Can Mo-30W be formed, bent or molded?
Bend, deep-draw or spin only warm (typically 200–500 °C, above the DBTT) with generous radii; cold forming of recrystallized material cracks readily.
What is the maximum service temperature of Mo-30W?
Mo-30W is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Mo-30W-SR and Mo-30W-CW?
SR is the default condition — standard commercial condition for rod, plate and machined parts: worked fibre structure retained, internal stresses removed, best balance of strength and workability. CW: choose for maximum room-temperature strength and stiffness in thin sheet, foil, wire and electrodes where no high-temperature exposure will recrystallize the part. Yield strength is 620 MPa in SR versus 950 MPa in CW.
How much does Mo-30W cost?
Mo-30W is a high-cost refractory metal ($$$$), 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 B387 — Molybdenum and Molybdenum Alloy Bar, Rod and Wire — ASTM International (2018)
- ASTM B386 — Molybdenum and Molybdenum Alloy Plate, Sheet, Strip and Foil — ASTM International (2018)
- ASM Specialty Handbook / ASM Handbook Vol. 2 — Refractory Metals and Alloys — ASM International (1990)
- Molybdenum-tungsten (MoW30) material datasheet — Plansee SE (2023)
- Mo-30W alloy for zinc and glass industry applications — Elmet Technologies / Midwest Tungsten (2022)
- GB/T 3462 / GB/T 4181 (2017)
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.