The Category of Tungsten Wires

Aug. 24, 2010 - PRLog -- Tungsten is the most widespreading used as refractory metals. In wire form, it is essential for the production of lighting products and other goods where its high temperature properties are of use. Tungsten wires are including black tungsten wires,clean tungsten wires and tungsten rhenium wires and so on.
Black Tungsten Wires                                              
The products are featured with minimum formation at high temperatures, high recrystallization temperatures, uniformity in dimension and excellent coil ability. For tungsten rod weighing 3kg/pc, its rough welding tungsten wire weighing 5kg/pc. Customers are allowed to choose various types of tungsten wire in accordance with their specific applications.
The important applications are for the production of coiled incandescent lamp filaments, cathode and support structures for power tubes, heating elements for high temperature furnaces and evaporation sources in metallizing processes. Thicker wire sizes, straightened, finish-ground and cut into rod pieces are widely used for glass-to-metal seal lead parts in the lighting and electronic industries.
Clean Tungsten Wires                                              
Clean tungsten wires are the surface of electrolytic polished tungsten wire, they shall be smooth, clean, gray silver with metal luster. The tungsten wire features excellent formability, long life and super lighting efficiency. Mainly applied for making various electron tubes, H series auto lamp, halogen lamp and other special lamp.
Tungsten Rhenium Wires
Tungsten-rhenium wire doped with rhenium, which has much better ductility and stability than pure tungsten in high temperature.
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.
Once tungsten wire used at high temperature after recrystallization, it becomes quite fragile. And it can be easily broken under the condition of shaking and vibrating. In some electric light source products require high reliability, in order to prevent fragmentation of lamp filament, tungsten wire often doped 3 to 5% rhenium, known as the tungsten rhenium wire which can make the extension of tungsten-brittle transition temperature decreased to room temperature or below room temperature.
Tungsten wire has fiber structure, when the temperature reaches 1500-1600 ℃, the tungsten filament would turn, and cause high-temperature sag. All wires showed here are doped tungsten wires and manufactured by the high tech of doping, acid washing, isostatic pressing, PLC controlled direct sintering, swaging and auto feeding.