Rhenium has several unique properties as follows: High melting temperature, Extreme resistance to chemical erosion Ability to maintain ductility after re-crystallization, High electrical resistivity over a wide temperature range, low vapor pressure. So when compared to pure tungsten wire, it has follow advantages: Greater tensile strength, Higher re-crystallization temperature, Greater specific resistance, Superior hot strength and vibration strength, No brittleness in re-crystallized condition, Higher thermal stability
Tungsten rhenium wire has much better ductility and stability than pure tungsten wire in high temperature. Thermocouple made of Re-W are used for measuring temperature up to 2,200oC. Widely used for heater elements, thermocouple wires, furnace shielding, heat sink, welding / medical application as well as for long-life light bulbs making. And suitable for TCD filaments, Gas chromatography detector filaments, electron-gun, electron tube application. Tungsten rhenium wire is used for heating elements in high temperature furnaces, thermocouples and in electronics. Its advantage is its ability to maintain greater ductility compared to tungsten after exposure to extremely high temperature.Tungsten wire has fiber structure, when the temperature reaches 1500-1600 ℃, the tungsten filament would turn, and cause high-temperature sag. To improve the quality of tungsten wire, it is always mixed some additives during sintering procession, such as Na2O, K2O, SiO2, ThO to enhance the capacity of high-temperature creep resistance and high temperature anti-sag of tungsten wire. In order to improve the tenacity of tungsten wire and prevent the deformation under high temperature, it usually added some oxides, such as silica, alumina, potassium and so on.
Rhenium can improve tungsten’s intensity and plasticity. And a few rhenium (3%~5%) can rise the re-crystallization starting temperatures about 300℃～500℃Tungsten rhenium wire has good intensity in room temperature and high temperature, and can plastic easily after re-crystallization. Moreover, it has big resistivity, low resistance coefficient, antioxidant and carbonation, ect.