Tungsten needle is an elongated structure made of pure tungsten or tungsten alloy of tungsten products obtained. Welding techniques may be used in the electrode material, the instrument can also be used as probes. There are high temperature, electrical conductivity and good.

Tungsten needles are manufactured by glow discharge under the conditions of a carbonyl group formed by tungsten vapor. Needle growth phenomena in tungsten substrate indoor temperature 1500 ° K range, but when the needle form above or below ~1100 ° K generated and crystalline state are different. At lower temperatures, the shape of the tungsten particulate agglomerate product as branches, as at higher temperatures the beard.

Tungsten needle electrode is an instrument for the families of refractory alloy composition, electrode say there is a blunt and pointed at the end, by the rotation axis perpendicular to the ultra-sharp electrode cylindrical refractory alloy composition, and may revoke and replace the melting cycle oxidant pool bar.

Application:

Mainly used for engraving metal tungsten needle surface, cutting operation and a single particle in collodion particles. Since these pins are very fragile, so it is often bent or broken. Upon completion of the cutting particles require manual operation. These particles are tungsten needles used not only for cutting, but also for blown crystal and glass blanks.

Classification:

Tungsten needle can be divided according to the shape of a round rod with a pointed tungsten tungsten needle and needle.

1.Round rod:

Round slender rod tungsten needle structure, rich metallic surface. For welding electrode. TIG is home to the fastest growing technology, the most widely used welding technology. Especially GTAW, has become a variety of metal structures essential means of welding. Welding, generated in the arc between the tungsten electrode and the workpiece, the filler metal is fed from one side, under the action of heat of the arc, the molten filler metal and workpieces together to form a weld. In order to prevent the electrode melting and burning, welding current is not too large, and therefore, TIG welding is usually applied to thin 4mm or less, such as docking tube connecting tube and tube sheet.

Tungsten needle with a tip of the probe is mainly used for instrument use. Such as digital four-probe tester, the device is the use of four-probe measurement principle of multi-purpose integrated measurement equipment. The instrument in accordance with the national standard monocrystalline physical testing methods and reference to ASTM standards designed specifically for testing semiconductor material resistivity and sheet resistance (sheet resistance) of special equipment. Applicable to semiconductor materials factory, semiconductor device factory, research institutes, universities semiconductor material resistance performance testing.

Dimensions:

Tungsten needle selection of different sizes, depending on usage.
Length of 20mm-150mm diameter 0.5mm-10mm.

There are two main tungsten needle production process: a metal injection molding process, two drawing molding process.

The basic process is the metal injection molding process, first a uniform solid powder kneaded with an organic binder, after granulation in a plasticized state under heating, using an injection molding machine into the mold cavity solidifying-forming. Then use chemical or thermal decomposition method blanks in the shape of the binder removal, the final densification tungsten needle to get the final product.

Brushed metal molding process is heated to the plastic raw materials, and then stretched to the desired diameter, and finally cut through cooling.