A tungsten filament is a thin strand of the metal which glows very brightly when an electric current is passed through it. When coiled and sealed inside a glass container filled with an inert gas, a tungsten filament can glow brightly enough to light up a room. It was the inclusion of a tungsten filament in his electrical lighting system that resulted in the world giving Thomas Edison credit for inventing the electric light bulb when in fact dozens of scientists had been experimenting with electric light.
Tungsten is an element (Symbol: W; Atomic Number 74) discovered in the late 18th century. Almost twice as dense as lead, it has the highest melting point of all the metals at 6192 ° F (3422 ° C); of all the elements, only carbon’s melting point is higher. These properties make tungsten very useful not only in electric technology, but also for military applications such as hardening weapons. Another use of tungsten is as a component of jewelry, where it’s combined with other materials to form very hard and lustrous compounds, although they can be brittle.
When Thomas Edison and other scientists were working on developing the electric light bulb, they experimented with a number of materials for the light-producing filament. Until the early 20th century, the most successful incandescent light bulbs utilized a filament of carbonized bamboo, which lasted about 1,200 hours. Edison wasn’t the first to use tungsten, which was introduced as an incandescent light bulb filament in Europe in 1904.
In 1906, Edison’s company General Electric (GE) developed a process for making pure tungsten flexible enough to draw into a coiled wire. Using a coiled wire allowed GE to increase the surface area of tungsten that would be inside the bulb. By 1911, the company was manufacturing and selling light bulbs using the new filaments, which outlasted all others. Advances in this technology continued almost uninterrupted, so that the cost of operating an incandescent bulb by the turn of the 21st century was less than 5% of what it was in 1911.
Tungsten Filament is arguably the key component of the incandescent lamp business.
The tungsten filament of a vacuum incandescent lamp is heated to temperatures where visible light is emitted by resistance heating. The filament acts as an electrical resistor, which dissipates power proportional to the voltage applied, times the current through the filament.
The Tungsten Filament is quite sturdy and provides stable and uniform electron emission, primarily used in scanning electron microscopy.
Application of Tungsten Filament:
1.Tungsten heater element and other heater components in semiconductor.
2.High temperature lamp filament, stock-resistance filament, double helix filament, etc.
3.Electric incandescent lamp filament, fluorescent light filament, etc.