At Ananka Fasteners Pvt Ltd, we manufacture and supply fasteners certified to ASTM B708. CORRECTION: ASTM B708 covers tantalum and tantalum alloy PLATE, SHEET, and STRIP (not ‘plate washers’). This wrought flat product is the stock from which tantalum washers, gaskets and blank hardware are fabricated for highly corrosive acid and chemical-process service.
CORRECTION: ASTM B708 covers tantalum and tantalum alloy PLATE, SHEET, and STRIP (not ‘plate washers’). This wrought flat product is the stock from which tantalum washers, gaskets and blank hardware are fabricated for highly corrosive acid and chemical-process service.
| Grade / Class | UNS / Designation | Type / Notes |
|---|---|---|
| Type 1 (EB tantalum) | UNS R05200 | Electron-beam melted unalloyed Ta |
| Type 2 (powder/arc Ta) | UNS R05400 | Sintered/arc-cast unalloyed Ta |
| Type 3 Ta-2.5W | UNS R05252 | Tantalum-2.5% tungsten alloy |
| Type 4 Ta-10W | UNS R05255 | Tantalum-10% tungsten alloy |
Minimum mechanical requirements per ASTM B708.
| Grade / Class / Condition | Tensile Strength, min | Yield Strength, min | Elongation, min % | Hardness |
|---|---|---|---|---|
| R05200 (annealed) | 25 ksi (170 MPa) | 20 ksi (138 MPa) | 25 | N/A |
| R05400 (annealed) | 30 ksi (207 MPa) | 25 ksi (172 MPa) | 20 | N/A |
| R05252 Ta-2.5W (ann) | 50 ksi (345 MPa) | 40 ksi (275 MPa) | 20 | N/A |
| R05255 Ta-10W (ann) | 85 ksi (585 MPa) | 75 ksi (515 MPa) | 15 | N/A |
| Grade | Key Composition, % |
|---|---|
| R05200 / R05400 | Ta >=99.8 (bal), Nb <=0.10, W <=0.05, O/N/C/H low interstitials |
| R05252 | Ta bal, W 2.0-3.5 |
| R05255 | Ta bal, W 9.0-11.0 |
UNS R05200/R05400/R05252/R05255; ASTM B521 (tube), B365 (rod) companion Ta specs
For the official ASTM International standards catalogue, see the ASTM International standards listing. This external reference is provided for standards identification; the purchaser should verify the current edition applicable to the order.
We supply ASTM B708 fasteners — bolts, screws, studs, nuts and washers as applicable — for energy, petrochemical, marine, structural and general engineering service, in a full range of sizes and finishes.
For technical documentation and quotations, buyers can also review the Ananka Fasteners manufacturing and supply range or contact the team through the fastener enquiry and technical support page.
Ananka Fasteners supplies every lot with full material traceability and third-party testing on request.
CORRECTION: ASTM B708 covers tantalum and tantalum alloy PLATE, SHEET, and STRIP (not ‘plate washers’). This wrought flat product is the stock from which tantalum washers, gaskets and blank hardware are fabricated for highly corrosive acid and chemical-process service.
Ananka Fasteners supplies Type 1 (EB tantalum), Type 2 (powder/arc Ta), Type 3 Ta-2.5W, Type 4 Ta-10W to ASTM B708. See the Grades / Classes Covered table above for full details of each grade.
Minimum tensile strength, yield strength, elongation and hardness requirements vary by grade — see the Mechanical Properties table above for the complete breakdown.
We supply ASTM B708 fasteners — bolts, screws, studs, nuts and washers as applicable — for energy, petrochemical, marine, structural and general engineering service, in a full range of sizes and finishes.
Yes. For a quotation, provide the required fastener type, grade, nominal size, dimensional standard, quantity and any inspection or certificate requirements.
Need a fastener released to ASTM B708 for an industrial project? Send the required fastener type, grade, size, quantity and certification requirements to Ananka Fasteners. Our team can review the requirement and provide technical and commercial information for standard or custom configurations.
Recommended RFQ details: ASTM B708 requirement, material grade, fastener type, nominal size, dimensional standard, quantity, inspection requirements and EN 10204 certificate requirements where applicable.
Data compiled per ASTM B708 and industry references; provided for reference only — confirm against the current edition of the standard and certified mill test reports before design use.
