UNS R05200 represents commercially pure, unalloyed Tantalum produced via electron-beam (EB) or vacuum-arc reduction (VAR) melting. In the realm of industrial metallurgy, Tantalum is the ultimate failsafe. It possesses a legendary, glass-like immunity to chemical attack, exhibiting a corrosion rate of virtually zero in boiling concentrated hydrochloric, nitric, and phosphoric acids. Where premium superalloys like Titanium, Hastelloy, and Zirconium dissolve or pit, Tantalum survives indefinitely.
While it is incredibly dense (over twice the weight of steel) and possesses a staggering melting point of 2,996°C (5,425°F), pure Tantalum is surprisingly ductile at room temperature. Because it mirrors the chemical inertness of glass, UNS R05200 fasteners are the globally mandated hardware for patching and repairing glass-lined chemical reactors, securing internal components in aggressive pharmaceutical synthesis vessels, and serving in critical biocompatible medical implants.
| Material Classification | Commercially Pure Tantalum (EB or VAR Melted) |
|---|---|
| UNS Designation | R05200 |
| Microstructure | Body-Centered Cubic (BCC) |
| Magnetic State | Completely Non-Magnetic |
| Density | 16.60 g/cm³ (0.600 lb/in³) — Exceptionally Heavy |
| Size Range | Metric: M2 to M24 | Imperial: #2 to 1" |
| Primary Attribute | Glass-Like Immunity to Boiling Concentrated Acids |
Contains detailed installation procedures for glass-lined vessel repair plugs, exact PTFE washer compression limits, and comprehensive isocorrosion charts for aggressive acid concentrations.
⬇ DOWNLOAD DATASHEETTantalum is one of the most expensive industrial metals on earth, heavily categorized as a conflict mineral. Ananka provides absolute, audited supply-chain transparency. Every shipment includes EICC-compliant origin tracing and stringent chemical verification to ensure interstitial impurities (like Oxygen and Nitrogen) are virtually nonexistent.
The R05200 specification mandates extreme purity. Tantalum has a violent affinity for absorbing gases (Oxygen, Nitrogen, Hydrogen) at high temperatures. If these gases contaminate the metal during melting or processing, the Tantalum becomes hopelessly brittle. Strict vacuum-arc or electron-beam melting ensures these interstitial impurities remain at parts-per-million (ppm) levels.
| Tantalum (Ta) | Niobium (Nb) | Oxygen (O) | Carbon (C) | Nitrogen (N) | Iron (Fe) / Tungsten (W) |
|---|---|---|---|---|---|
| 99.90 Min | 0.10 Max | 0.015 Max | 0.010 Max | 0.010 Max | 0.010 Max / 0.05 Max |
| Mechanical Property | Typical Limits (Fully Annealed Temper) |
|---|---|
| Tensile Strength | 30,000 - 45,000 psi (205 - 310 MPa) |
| Yield Strength | 20,000 - 30,000 psi (138 - 205 MPa) |
| Elongation (in 2 inches) | 20% - 30% |
| Hardness (Vickers) | ~ 110 HV (approx. 60 HRB) |
| Standard / System | Designation |
|---|---|
| ASTM Specifications | ASTM B365 (Rod and Wire), ASTM B390 |
| Common Trade Names | Commercially Pure Tantalum, Unalloyed Ta |
| Medical Specifications | ASTM F560 (Unalloyed Tantalum for Surgical Implant) |
| European Equivalent | Ta99.9 (DIN 2.5220) |
| Mating Bolts/Studs | Internal Threads (Nuts) | Washers / Sealing Components |
|---|---|---|
| R05200 Machined Studs & Screws | R05200 Precision Hex Nuts | Virgin PTFE / Teflon Gaskets & Washers |
CRITICAL WARNING: Pure Tantalum is notoriously soft, "gummy," and highly prone to catastrophic thread galling. Threading a Tantalum nut onto a Tantalum bolt without severe friction is extremely difficult. They are rarely torqued highly. In chemical patching applications, Tantalum hardware is almost always mated with thick PTFE (Teflon) washers; the goal is simply to compress the PTFE to form a liquid-tight seal, not to generate heavy structural clamping force.
| Nominal Diameter | Threads Per Inch (UNC) | Max Target Torque (in-lbs) — PTFE Lubricated |
|---|---|---|
| #10 | 24 | 12 - 15 |
| 1/4" | 20 | 30 - 35 |
| 3/8" | 16 | 80 - 90 |
| 1/2" | 13 | 180 - 200 |
While Titanium and Hastelloy (Nickel alloys) are excellent in many corrosives, they have strict temperature and concentration limits. For example, in boiling 98% Sulfuric Acid or hot concentrated Hydrochloric Acid, Titanium and Hastelloy will rapidly corrode. Tantalum's natural oxide layer is virtually impenetrable by these acids. If the environment destroys premium superalloys, Tantalum is the final line of defense.
Yes. While it is immune to almost everything, Tantalum has a severe vulnerability to Hydrofluoric Acid (HF), hot fuming Sulfuric acid (Oleum), and strong, hot alkaline solutions (like concentrated Sodium Hydroxide). Exposure to Hydrofluoric acid will cause rapid, violent corrosion and hydrogen embrittlement of the fastener.
Glass-lined steel reactors are used to synthesize highly aggressive chemicals, but the glass lining can chip if accidentally struck by a dropped tool. Rather than replacing a $100,000 vessel, maintenance crews drill out the chip, tap the steel beneath it, and thread a Tantalum repair stud (often called a "spud") into the hole. They then place a thick PTFE gasket over the stud and tighten down a Tantalum nut. Because Tantalum and PTFE match the chemical resistance of the glass, the reactor is safely sealed and returned to service.
