Tungsten-Rhenium Thermocouples and Wire
Request Tungsten-Rhenium Thermocouple Pricing
Auremo LLC, 505 Ellicott St, Buffalo, NY 14203, handles tungsten-rhenium thermocouple wire inquiries for U.S. customers. Call +1 716 910 04 21 or send the W-Re pair, diameter, length and quantity.
Available product forms
- matched tungsten-rhenium thermoelement wire
- wire diameters and spool lengths by specification
- rod or heavier sections subject to availability
- custom quantities and documentation requirements
Information to include in your request
Please provide the governing standard or grade, product form, dimensions and tolerances, quantity, delivery ZIP code and required documentation. Pricing and availability are confirmed individually for each inquiry.
Frequently asked questions
How is the price for tungsten-rhenium thermocouples and wire confirmed?
Prices are provided on request and depend on the exact grade or standard, dimensions, tolerances, quantity, documentation and freight requirements.
Can non-standard dimensions be requested?
Yes. Include a drawing or dimensional requirements. Availability and manufacturing or sourcing feasibility are confirmed with the quotation.
What is the typical delivery time in the United States?
Typical U.S. delivery is 2–3 weeks after order confirmation. The final lead time and delivery terms are stated in the quotation for the selected material, quantity and destination.
Related materials and references
Tungsten wire · Tungsten products · Rhenium material reference
Equivalent
| Grade | analogue | W. Nr. | Aisi Uns | En | Order |
|---|---|---|---|---|---|
| VR5 | WRe20 | Buy from stock, view availability | |||
| BP20 | WRe20 | Buy from stock, view availability |
Tungsten-rhenium thermocouple specification review
A request should identify the required tungsten-rhenium thermoelement pair, wire diameter, length or spool requirement, calibration or governing specification, temperature range, atmosphere, insulation or sheath requirements, documentation and quantity. The existing technical record describes W-Re 5/20-type combinations; the exact designation and compatibility with the customer’s instrument and process must be confirmed before quotation.
Doping Features
The tungsten rhenium thermocouple is capable of measuring the highest temperatures. In doing so, a number of factors should be taken into account. The ductility and recrystallization temperature increase towards the positive VR electrode due to the admixture of five percent rhenium. To obtain the highest possible thermo-EMF, the content of rhenium in the negative electrode should be as different as possible from the proportion in the positive. However, with an increase in the proportion of rhenium to 32% or more in the composition of the alloy at t ° above 1100 ° C, intermetallic phases begin to form, which leads to a drop in the accuracy of the readings. In addition, this alloy will be inhomogeneous; with high heating, rhenium will begin to evaporate, which also increases the error. The accuracy of thermocouples VR5 and VR20 at a temperature of 900−2100°C decreases linearly. To increase stability, tungsten-rhenium thermocouple is alloyed with silicon-alkali additives (KCl 0.1−0.5%, Al 0.1−0.5%, 0.1−0.5% SiO 2), which is almost three times reduces the error in the measurement process.
| Number | Brand | %Re | Section (mm) | Rental type | price |
|---|---|---|---|---|---|
| 1 | BP5 | 5% | Ø 0.35−0.5 | wire | negotiable |
| 2 | BP20 | 20% | Ø 0.35−0.5 | wire | negotiable |
| 3 | VR5 | 5% | Ø more than 0.5 | bar | negotiable |
Calibration and accuracy
Calibration and allowable error depend on the thermoelement pair, wire homogeneity, temperature range, atmosphere and measurement system. Confirm the required calibration, tolerance class and documentation for the intended installation.
Percentage fluctuations
According to the technical specifications for the thermal electrode wire, fluctuations in the content of rhenium in the alloy are not more than 0.5%, the proportion of impurities is not more than 0.1%. Therefore, different batches of wire have a spread of thermal electromotive force. Up to t ° 1500 ° C in one coil of wire, a spread of thermo-EMF up to 50 μV is allowed.
Production
In the 80s of the last century, the production of thermoelectrode wire VR20 and VR5 (VAR5) was approximately 150 kilograms per year. Thermoelectrode wire has been used for various jobs by aircraft design bureaus and research institutes in the technology of composite materials production. The main consumer of this material was the metallurgical industry.
Wire is produced by powder metallurgy. A mixture of tungsten powder and ammonium salts (NH 4 ReO 4) perrhenate is pressed into rods, after which they are fused and rolled into a wire. It was not possible to carry out cardinal optimization of the thermoelectric characteristics of the thermocouple, due to the «floating» percentage of rhenium in the composition of the alloy. Despite this, there have been some recent advances in micrometallurgy, thanks to nano-alloying additives and improvements in metal analysis.
Usage
They are used only in an inert atmosphere or in a vacuum. To expand the field of application of thermocouples, a sealed special case was developed, which is filled with an inert gas for protection in oxidizing and carbon environments (for example, in vacuum furnaces with graphite heaters).
Hermetic thermal converter, located in a molybdenum case, is designed to control the sintering mode of powder pellets in a vacuum furnace. The operating life of such a converter is at t°1750°C, up to 1000 hours in an aggressive environment. Other VRs have also been developed - sealed transducers in cases made of leucosapphire (a single crystal of aluminum), whose service life at a temperature of 1600 °C in oxidizing environments is 2−3 thousand hours. They are also used in thermal probes to control the melting of salts, glass and metals.
Such thermal converters are used in very aggressive environments, and the working life directly depends on the durability of its protective cover. If in the range of 1000 - 1700 ° C the permissible error should be 0.5%, a platinum-rhodium thermocouple is used.
