Nature:

A gray-black metal with a metallic luster (body-centered cubic crystal). Melting point3400℃. Boiling point5555℃。

The hardness of tungsten is the highest among metals, and the hardness of sintered tungsten rods is200～250,The tungsten rod after rotary swaging is350~400It is soluble in a mixed acid of nitric acid and hydrofluoric acid. It melts when combined with a mixture of sodium hydroxide and sodium carbonate. It is slightly soluble in nitric acid, sulfuric acid, and aqua regia; insoluble in water, hydrofluoric acid, and potassium hydroxide. Tungsten has two allotropes.aandBUnder standard temperature and normal pressure,aThe type is a stable body-centered cubic structure.BType tungsten can only appear in the presence of oxygen.630Stable below ℃.630℃以上又转化为aTungsten, and this process is irreversible.

Usage:

Tungsten is primarily used in the production of cemented carbide and ferrotungsten. Tungsten, combined with chromium, molybdenum, and cobalt, forms heat-resistant and wear-resistant alloys used for manufacturing cutting tools, metal surface hardening materials, gas turbine blades, and combustion tubes. Tungsten, along with tantalum, niobium, and molybdenum, forms refractory alloys. Tungsten-copper and tungsten-silver alloys are used as electrical contact materials. High-density tungsten-nickel-copper alloys are used as radiation shielding screens. Tungsten wires, rods, and sheets are used to manufacture components for light bulbs, electronic tubes, and electrodes for arc welding. Tungsten powder can be sintered into filters with various porosities.FW-1Used for large slabs and tungsten-rhenium thermocouple raw materials.FW-2Used for contact alloys and high-density shielding materials.FWP-1Used for plasma spray coating materials.

Tungsten powder is the primary raw material for processing powder metallurgy tungsten products and tungsten alloys. Pure tungsten powder can be made into processed materials such as wires, rods, tubes, and plates, as well as shaped products. When mixed with other metal powders, tungsten powder can produce various tungsten alloys, such as tungsten-molybdenum alloys, tungsten-rhenium alloys, tungsten-copper alloys, and high-density tungsten alloys. Another important application of tungsten powder is the production of tungsten carbide powder, which is further used to manufacture cemented carbide tools, such as lathe tools, milling cutters, drill bits, and molds.