WNiFe Tungsten Heavy Alloys belong to the Tungsten Heavy Alloy (WHA) family and contain 90–97 wt% tungsten with a ductile nickel–iron binder phase (typically Ni:Fe ≈ 7:3 or 8:2). These alloys combine the density of tungsten with excellent room-temperature ductility and machinability.
Unlike pure tungsten, WNiFe alloys are tough, structurally reliable, and suitable for complex machined components. Their two-phase composite microstructure consists of hard tungsten grains embedded in a ductile Ni–Fe matrix.
Strengthening & Metallurgical Behavior
Microstructure
• Spherical tungsten grains (20–60 µm)
• Continuous Ni–Fe binder matrix
• Controlled W–W contiguity is critical
Strengthening Mechanisms
✔ Load transfer from binder to tungsten
✔ Solid-solution strengthening of Ni–Fe matrix
✔ Grain boundary strengthening
✔ Optional cold working and swaging
Failure Mode
• Ductile fracture through binder phase
• Tungsten grain pull-out at high strain
Refining & Processing Properties
Manufacturing Route
• High-purity W, Ni, Fe powders
• Powder blending and pressing
• Liquid-phase sintering (~1480 °C)
• Optional HIP (Hot Isostatic Pressing)
• Swaging / forging / heat treatment
• CNC machining to final shape
Machinability
✔ Significantly easier than pure tungsten
✔ Machinable using carbide tools
✔ Comparable to hardened steel
Available Forms
✔ Rods & bars
✔ Plates & sheets
✔ Blocks & cubes
✔ Cylinders & slugs
✔ Precision-machined parts
✔ Counterweights & balance weights
Supplied in sintered, swaged, or heat-treated conditions.
Key Characteristics
✔ Very high density (17–18.8 g/cm³)
✔ Excellent room-temperature ductility
✔ High tensile and yield strength
✔ Good corrosion resistance
✔ Superior vibration damping
✔ Excellent radiation shielding
✔ Dimensional stability
Limitations
⚠ Lower melting point than pure tungsten
⚠ Binder phase limits extreme-temperature use
Typical Applications
Defense & Aerospace
Kinetic energy penetrators, missile ballast, inertial systems
Industrial
Vibration dampers, counterweights, flywheel masses
Medical & Nuclear
Radiation shielding, collimators, gamma absorbers
Automotive & Motorsports
Crankshaft balance weights, racing ballast
Oil & Gas
Downhole weights, directional drilling components
Material Comparison
| Material | Density (g/cm³) | Ductility | Machinability | Max Temp |
|---|---|---|---|---|
| Pure Tungsten | 19.3 | Poor | Very Poor | Very High |
| WNiFe | 17–18.8 | Excellent | Good | Medium |
| WCu | 11–17 | Moderate | Good | Medium |
| WRe | 19.3 | Moderate | Poor | Very High |
Why Choose WNiFe Tungsten Alloys?
Choose WNiFe (90–97%) when very high density must be combined with toughness, machinability, and impact resistance. These alloys offer the best balance of density, strength, and ductility among tungsten-based materials.