Tungsten Alloy WHA-90-HT
Heat-treated state
HT = sintered + vacuum/hydrogen-free heat treated
Choose when ductility and impact energy must be restored by removing sintering hydrogen and residual stress, e.g. thin-web machined parts and threaded components.
Values for the HT condition
Other WHA-90 tempers and conditions
WHA-90 is listed in 4 conditions; see the grade overview at WHA-90.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
HTThis page Sintered + vacuum/hydrogen-free heat treated | Choose when ductility and impact energy must be restored by removing sintering hydrogen and residual stress, e.g. thin-web machined parts and threaded components. | 610 | 920 | 20 | 25 HRC | 15 % IACS |
SinteredDefault as liquid-phase sintered (default) | Standard stocked condition for counterweights, shielding and general machined parts where ASTM B777 Class 1 minimums suffice. | 620 | 900 | 10 | 26 HRC | — |
Hot isostatic pressed | Pick when residual porosity must be closed for maximum ductility, toughness and reliable ultrasonic/radiographic acceptance (aerospace balance weights, penetrators). | 650 | 960 | 22 | 27 HRC | — |
Swaged / cold worked | Use for high-strength small-diameter rod and penetrator cores where strength and hardness matter more than elongation. | 1,050 | 1,250 | 5 | 38 HRC | — |
What is WHA-90-HT?
WHA-90-HT is WHA-90 heat treated to HT — choose when ductility and impact energy must be restored by removing sintering hydrogen and residual stress, e.g. thin-web machined parts and threaded components. WHA-90-HT has a yield strength of 610 MPa (88.5 ksi) and a tensile strength of 920 MPa (133 ksi) — weaker than 72% of tungsten alloy grades. Elongation at break is 20% and the elastic modulus is 350 GPa (50.8 Msi). WHA-90-HT has a density of 17 g/cm³ (0.614 lb/in³), lighter than 74% of tungsten alloy grades. It melts at 1,450°C (2,642 °F). Sintered is the default condition FabDigit quotes; HT is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 20%, better than 105% of tungsten alloy grades
- Tough — resists crack growth — 85 MPa·√m (77.4 ksi·√in), better than 105% of tungsten alloy grades
- Forms and bends easily — 15/100, better than 90% of tungsten alloy grades
- Easy to machine — 28/100, better than 86% of tungsten alloy grades
- Low embodied carbon — 22 kg CO₂/kg, better than 79% of tungsten alloy grades
Limitations
- Low stiffness — 350 GPa (50.8 Msi), worse than 86% of tungsten alloy grades
- Needs corrosion protection — 45/100, worse than 86% of tungsten alloy grades
- Poor heat conductor — 90 W/m·K (52 BTU/hr·ft·°F), worse than 81% of tungsten alloy grades
WHA-90-HT properties
Typical room-temperature values for WHA-90-HT; 23 are specific to this condition. Other listed values are WHA-90 reference data and may not represent this condition. Bars are the position among tungsten alloy grades.
Physical2
WHA-90-HT has a density of 17 g/cm³ (0.614 lb/in³), lighter than 74% of tungsten alloy grades. It melts at 1,450°C (2,642 °F).
Mechanical16
WHA-90-HT has a yield strength of 610 MPa (88.5 ksi) and a tensile strength of 920 MPa (133 ksi) — weaker than 72% of tungsten alloy grades. Elongation at break is 20% and the elastic modulus is 350 GPa (50.8 Msi).
Thermal4
WHA-90-HT is rated for continuous service to 500°C (932 °F). It conducts heat at 90 W/m·K (52 BTU/hr·ft·°F), worse than 81% of tungsten alloy grades. Thermal expansion is 5.1 µm/m·K (2.83 µin/in·°F).
Electrical3
WHA-90-HT conducts electricity at 15 % IACS, worse than 69% of tungsten alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 86% of tungsten alloy grades.
Sustainability4
Producing a kilogram of WHA-90-HT takes about 320 MJ of energy and emits 22 kg of CO₂ — less than 81% of tungsten alloy grades. Typical recycled content is 30%.
Manufacturability7
WHA-90-HT's machinability is poor (28/100, better than 86% of tungsten alloy grades); weldability poor (18/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with WHA-90-HT
Is WHA-90 easy to machine?
Machine like a hard, abrasive cast iron: rigid setup, negative-rake carbide or CBN, low speed (30–60 m/min) with heavy feed, generous coolant; grinding and EDM work well and are preferred for finish tolerances.
Can WHA-90 be welded?
Effectively non-weldable by fusion arc — the W skeleton melts far above the binder and cracks; join by brazing (Ag-Cu, Ni-based fillers), shrink fit, threading or mechanical fastening, with EB/laser only for shallow non-structural seams.
Can WHA-90 be formed, bent or molded?
No practical cold sheet forming; parts are pressed and liquid-phase sintered to near-net shape, with rotary swaging or light forging of rod for strength when needed.
What surface finishes work on WHA-90?
Not anodizable; grinding and lapping give mirror finishes, and electroless nickel, chrome plating or epoxy paint is used for corrosion and handling protection.
WHA-90 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 1 nominal 90 wt% tungsten | 89 – 91 | 90 |
| Nimatrix former, typical Ni:Fe ≈ 7:3 | 6 – 7.6 | 7 |
| Cooptional binder addition in some producer variants | ≤ 1 | |
| Other (C, O, Mo, Cu)total impurities/trace additions | ≤ 0.3 | |
| Febalance of Ni-Fe binder | ≥ 2.4 (balance) |
WHA-90-HT — frequently asked
What is WHA-90-HT used for?
WHA-90-HT is typically used for counterweights, vibration dampers and aerospace ballast. In short: workhorse heavy-metal tungsten.
What is the yield strength of WHA-90-HT?
WHA-90-HT has a typical yield strength of 610 MPa (88.5 ksi) and a tensile strength of 920 MPa (133 ksi) — weaker than 72% of tungsten alloy grades. Strength varies by condition: see the 4 listed tempers.
Is WHA-90-HT easy to machine?
Not especially — machinability is rated poor (28/100, better than 86% of tungsten alloy grades). Machine like a hard, abrasive cast iron: rigid setup, negative-rake carbide or CBN, low speed (30–60 m/min) with heavy feed, generous coolant; grinding and EDM work well and are preferred for finish tolerances.
Can WHA-90-HT be welded?
Not readily — weldability is rated poor (18/100). Effectively non-weldable by fusion arc — the W skeleton melts far above the binder and cracks; join by brazing (Ag-Cu, Ni-based fillers), shrink fit, threading or mechanical fastening, with EB/laser only for shallow non-structural seams.
What surface finishes work on WHA-90-HT?
Not anodizable; grinding and lapping give mirror finishes, and electroless nickel, chrome plating or epoxy paint is used for corrosion and handling protection.
Can WHA-90-HT be formed, bent or molded?
No practical cold sheet forming; parts are pressed and liquid-phase sintered to near-net shape, with rotary swaging or light forging of rod for strength when needed.
What is the maximum service temperature of WHA-90-HT?
WHA-90-HT 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 WHA-90 Sintered and WHA-90 Swaged?
Sintered is the default condition — standard stocked condition for counterweights, shielding and general machined parts where ASTM B777 Class 1 minimums suffice. Swaged: use for high-strength small-diameter rod and penetrator cores where strength and hardness matter more than elongation. Yield strength is 620 MPa in Sintered versus 1,050 MPa in Swaged.
Sources
- ASTM B777 Standard Specification for Tungsten Base, High-Density Metal — ASTM International (2022)
- AMS-T-21014 Tungsten Base, High Density Metal — SAE International (2018)
- Densimet / Inermet tungsten heavy alloy datasheets — Plansee (2023)
- ASM Handbook Vol. 2: Properties and Selection — Refractory Metals and Alloys — ASM International (1990)
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.