Tungsten Alloy 97W-2.1Ni-0.9Fe-SW
Finish state
ASTM B777 Class 4
SW = swaged / cold worked (≈10–20 % reduction) and aged
Specify for the highest strength and hardness in rod form (penetrator cores, high-load pins); ductility and toughness drop sharply and only simple round sections are available.
Values for the SW condition
Other 97W-2.1Ni-0.9Fe tempers and conditions
97W-2.1Ni-0.9Fe is listed in 3 conditions; see the grade overview at 97W-2.1Ni-0.9Fe.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stress relieved | Used for thin or close-tolerance machined parts where distortion after finish machining must be minimised. | 580 | 690 | 5 | 29 HRC | 15 % IACS |
Sintered + vacuum heat treated and quenched | Choose when maximum elongation and impact toughness are needed (kinetic-energy penetrators, dynamically loaded rotors); the anneal removes hydrogen and dissolves brittle intermetallics. | 610 | 730 | 7 | 28 HRC | 15 % IACS |
SWThis page Swaged / cold worked (≈10–20 % reduction) and aged | Specify for the highest strength and hardness in rod form (penetrator cores, high-load pins); ductility and toughness drop sharply and only simple round sections are available. | 900 | 1,000 | 2 | 38 HRC | 14 % IACS |
What is 97W-2.1Ni-0.9Fe-SW?
97W-2.1Ni-0.9Fe-SW is 97W-2.1Ni-0.9Fe supplied in the SW condition — specify for the highest strength and hardness in rod form (penetrator cores, high-load pins); ductility and toughness drop sharply and only simple round sections are available. 97W-2.1Ni-0.9Fe-SW has a yield strength of 900 MPa (131 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 69% of tungsten alloy grades. Elongation at break is 2% and the elastic modulus is 395 GPa (57.3 Msi). 97W-2.1Ni-0.9Fe-SW has a density of 18.5 g/cm³ (0.668 lb/in³), lighter than 62% of tungsten alloy grades. It melts at 1,455°C (2,651 °F).
Advantages
- Easy to machine — 32/100, better than 90% of tungsten alloy grades
- Tough — resists crack growth — 30 MPa·√m (27.3 ksi·√in), better than 81% of tungsten alloy grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 100% of tungsten alloy grades
- Needs corrosion protection — 45/100, worse than 86% of tungsten alloy grades
- Low electrical conductivity — 14 % IACS, worse than 76% of tungsten alloy grades
97W-2.1Ni-0.9Fe-SW properties
Typical room-temperature values for 97W-2.1Ni-0.9Fe-SW; 22 are specific to this condition. Other listed values are 97W-2.1Ni-0.9Fe reference data and may not represent this condition. Bars are the position among tungsten alloy grades.
Physical3
97W-2.1Ni-0.9Fe-SW has a density of 18.5 g/cm³ (0.668 lb/in³), lighter than 62% of tungsten alloy grades. It melts at 1,455°C (2,651 °F).
Mechanical16
97W-2.1Ni-0.9Fe-SW has a yield strength of 900 MPa (131 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 69% of tungsten alloy grades. Elongation at break is 2% and the elastic modulus is 395 GPa (57.3 Msi).
Thermal5
97W-2.1Ni-0.9Fe-SW is rated for continuous service to 300°C (572 °F). It conducts heat at 95 W/m·K (54.9 BTU/hr·ft·°F), worse than 71% of tungsten alloy grades. Thermal expansion is 4.3 µm/m·K (2.39 µin/in·°F).
Electrical3
97W-2.1Ni-0.9Fe-SW conducts electricity at 14 % IACS, worse than 76% of tungsten alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 86% of tungsten alloy grades.
Sustainability4
Producing a kilogram of 97W-2.1Ni-0.9Fe-SW takes about 380 MJ of energy and emits 26 kg of CO₂ — less than 62% of tungsten alloy grades. Typical recycled content is 25%.
Manufacturability8
97W-2.1Ni-0.9Fe-SW's machinability is poor (32/100, better than 90% of tungsten alloy grades); weldability not recommended (10/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 97W-2.1Ni-0.9Fe-SW
Is 97W-2.1Ni-0.9Fe easy to machine?
Machinable with sharp carbide or CBN tooling at low speed, high feed and rigid setups — treat like a hard cast iron; grinding and EDM are common for finishing, and dust must be collected (Ni/Co-free but respirable).
Can 97W-2.1Ni-0.9Fe be welded?
Effectively unweldable by fusion (binder segregation and cracking); join by silver/copper brazing, shrink fit, threading or adhesive, with EB/laser welding only for qualified special cases.
Can 97W-2.1Ni-0.9Fe be formed, bent or molded?
Net-shape by press-and-liquid-phase-sinter at 1450–1500 °C with ~18–20 % linear shrinkage; at 97 % W only limited rotary swaging of round bar is feasible, no sheet forming.
What surface finishes work on 97W-2.1Ni-0.9Fe?
No anodizing; parts are supplied ground, oiled, electroless-nickel or chrome plated, or epoxy-painted for humid and salt-spray environments.
97W-2.1Ni-0.9Fe 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 |
|---|---|---|
| WASTM B777 Class 4 requires 97 % W nominal; density class controls acceptance | 96.5 – 97.5 | 97 |
| Nibinder phase, Ni:Fe ≈ 7:3 | 1.8 – 2.4 | 2.1 |
| Cimpurity — carbon forms brittle carbides | ≤ 0.02 | 0.01 |
| Oimpurity | ≤ 0.02 | 0.01 |
| Febalance of Ni+Fe binder | ≥ 0.7 (balance) | — |
97W-2.1Ni-0.9Fe-SW — frequently asked
What is 97W-2.1Ni-0.9Fe-SW used for?
97W-2.1Ni-0.9Fe-SW is typically used for kinetic energy penetrators, aerospace balance weights, gyroscope rotors and radiation shielding. In short: near-maximum density, 18.5 g/cm³; highest-tungsten heavy alloy; low ductility, not weldable.
What is the yield strength of 97W-2.1Ni-0.9Fe-SW?
97W-2.1Ni-0.9Fe-SW has a typical yield strength of 900 MPa (131 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 69% of tungsten alloy grades. Strength varies by condition: see the 3 listed tempers.
Is 97W-2.1Ni-0.9Fe-SW easy to machine?
Not especially — machinability is rated poor (32/100, better than 90% of tungsten alloy grades). Machinable with sharp carbide or CBN tooling at low speed, high feed and rigid setups — treat like a hard cast iron; grinding and EDM are common for finishing, and dust must be collected (Ni/Co-free but respirable).
Can 97W-2.1Ni-0.9Fe-SW be welded?
Not readily — weldability is rated not recommended (10/100). Effectively unweldable by fusion (binder segregation and cracking); join by silver/copper brazing, shrink fit, threading or adhesive, with EB/laser welding only for qualified special cases.
What surface finishes work on 97W-2.1Ni-0.9Fe-SW?
No anodizing; parts are supplied ground, oiled, electroless-nickel or chrome plated, or epoxy-painted for humid and salt-spray environments.
Can 97W-2.1Ni-0.9Fe-SW be formed, bent or molded?
Net-shape by press-and-liquid-phase-sinter at 1450–1500 °C with ~18–20 % linear shrinkage; at 97 % W only limited rotary swaging of round bar is feasible, no sheet forming.
What is the maximum service temperature of 97W-2.1Ni-0.9Fe-SW?
97W-2.1Ni-0.9Fe-SW is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM B777 – Standard Specification for Tungsten Base, High-Density Metal — ASTM International (2022)
- ASM Handbook Vol. 2 – Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Tungsten Heavy Alloys) — ASM International (1990)
- Tungsten heavy alloy (W-Ni-Fe) grade datasheets — Plansee / Wolfmet / Mi-Tech Metals (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.