Welcome to LookChem.com Sign In|Join Free
  • or

7440-33-7

Post Buying Request

7440-33-7 Suppliers

Recommended suppliersmore

Product FOB Price Min.Order Supply Ability Supplier
Tungsten Manufacturer/High quality/Best price/In stock
Cas No: 7440-33-7
USD $ 3.0-3.0 / Kilogram 1 Kilogram 1-100 Metric Ton/Month Hangzhou Dayangchem Co., Ltd. Contact Supplier
Tungsten Manufacturer/High quality/Best price/In stock CAS NO.7440-33-7
Cas No: 7440-33-7
USD $ 1.0-3.0 / Metric Ton 1 Metric Ton 10 Metric Ton/Day Hebei yanxi chemical co.,LTD. Contact Supplier
Tungsten
Cas No: 7440-33-7
No Data No Data No Data Chemwill Asia Co., Ltd. Contact Supplier
7440-33-7 W Tungsten
Cas No: 7440-33-7
No Data 5 Gram 1 Kilogram/Day HENAN SUNLAKE ENTERPRISE CORPORATION Contact Supplier
TIANFU-CHEM CAS NO.7440-33-7 Tungsten
Cas No: 7440-33-7
No Data 1 Gram 1000 Kilogram/Month Henan Tianfu Chemical Co., Ltd. Contact Supplier
Manufacturer Supply AR 99% Tungsten in stock
Cas No: 7440-33-7
No Data 1 Kilogram 1 Metric Ton/Month Shaanxi Mingqi Chemical Co., Ltd Contact Supplier
Tungsten
Cas No: 7440-33-7
USD $ 10.0-1000.0 / Gram 10 Gram 8000 Kilogram/Month HUBEI AOKS BIO-TECH CO.,LTD Contact Supplier
Tungsten podwer high purity
Cas No: 7440-33-7
No Data 1 Kilogram 1000 Kilogram/Month Shaanxi WuZhiYuan Biological Technology Co.,Ltd Contact Supplier
Tungsten in stock with best price
Cas No: 7440-33-7
USD $ 100.0-150.0 / Kilogram 1 Kilogram 1000 Metric Ton/Day Wuhan Monad Medicine Tech Co.,LTD Contact Supplier
7440-33-7
Cas No: 7440-33-7
No Data 1 Kilogram 5000 Kilogram/Month Weifang Tansen Yiang international trading co., LTD Contact Supplier

7440-33-7 Usage

Chemical Properties

grey metal chunks or grey powder

Uses

Industrially tungsten is a very important metal having wide applications. This is due to many outstanding physical properties. Among all the metals, tungsten has the highest melting point and the lowest vapor pressure. Also at high temperatures it has the highest tensile strength. The metal has an excellent resistance to corrosion and attack by mineral acids. Also it has a thermal expansion comparable to that of borosilicate glass.
Tungsten is extensively used in alloy steel to impart high strength and hardness to steel. Heavy metal alloys with nickel, copper and iron, produced by powder metallurgy, can be made machineable and moderately ductile for applications as high-density materials. Tungsten carbides are extremely hard and are excellent cutting materials. They are used extensivly in the tool and die industry for drilling and cutting tools, sand blasting nozzels, armor-piercing bullets, and studs to increase traction of tires.
Among the nonferrous tungsten alloys, its alloys with copper and silver are used as electrical contacts and switches and with molybdenum in aerospace components.
Unalloyed tungsten has several major applications. An important use is in the electric lamp filaments for light bulbs. Also, it is used as electrodes in arcwelding, in heating elements for high-temperature furnaces, in electron and television tubes, in glass-to- metal seals, and in solar energy devices.

Reactions

Tungsten exhibits several oxidation states, +6 being most stable. Compounds of lower oxidation states show alkaline properties. They also are less stable than those produced in higher oxidation states. Tungsten exhibits remarkable stability to practically all substances at ambient temperature. The metal is not attacked by nonoxidizing mineral acid. Concentrated hydrochloric acid, dilute sulfric acid and hydrofluoric acid attack the metal very slightly even when heated to 100°C. Tungsten is stable to dilute or concentrated nitric acid under cold conditions. Cold acid passivates the surface forming a slight oxide film. Hot dilute nitric acid corrodes the metal, while hot concentrated acid slowly dissolves bulk metal but rapidly oxidizes metal in powder form. At room temperature, aqua regia oxidizes metal only on the surface forming tungsten trioxide. A hydrofluoric-nitric acid mixture rapidly oxidizes tungsten to its trioxide. Chromic acid-sulfuric acid mixture does not react with tungsten metal in ductile form at ambient temperatures.

Reactivity Profile

Tungsten is stable at room temperature. Very slowly attacked by nitric acid, sulfuric acid, and aqua regia. Dissolved by a mixture of hydrofluoric acid and nitric acid. No reaction with aqueous bases. Attacked rapidly by motlen alkaline melts such as Na2O2 or KNO3/NaOH. Vigorous reactions with bromine trifluoride and chlorine trifluoride. Becomes incandescent upon heating with lead oxide; becomes incandescent in cold fluorine and with iodine pentafluoride. Combustible in the form of finely divided powder and may ignite spontaneously.

Physical Properties

Grayish-white metal; body-centered cubic crystalline structure; density 19.3 g/cm3; melts at 3,422°C; vaporizes at 5,555°C; vapor pressure 1 torr at 3,990°C; electrical resistivity 5.5 microhm-cm at 20°C; modulus of elasticity about 50 to 57 × 106 psi (single crystal); Poisson’s ratio 0.17; magnetic susceptibilty +59 × 10–6; thermal neutron absorption cross section 19.2 + 1.0 barns (2,200m/sec); velocity of sound, about 13,000 ft/sec; insoluble in water; practically insoluble in most acids and alkalies; dissolves slowly in hot concentrated nitric acid; dissolves in saturated aqueous solution of sodium chlorate and basic solution of potassium ferricyanide; also solubilized by fusion with sodium hydroxide or sodium carbonate in the presence of potassium nitrate followed by treatment with water.

Purification Methods

Clean the solid with conc NaOH solution, rub it with very fine emery paper until its surface is bright, wash it with previously boiled and cooled conductivity water and dry it with filter paper. [Hein & Herzog in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II p 1417 1965.]

History and Occurrence

The discovery of tungsten occurred in the 1780’s. Peter Woulfe, in 1779, while examining the mineral now known as wolframite, established that it contained a new substance. Around the same time, Swedish chemist Carl Wilhelm Scheele was investigating another mineral, scheelite. This mineral was known at that time as tungsen, which in Swedish meant heavy stone. Scheele, in 1781, determined that tungsen contained lime and a new acid similar to molybdic acid. This new acid was tungstic acid. Scheele and Bergman predicted that reduction of this acid could produce a new metal. Two years later in 1783, J. J. de Elhuyar and his brother F. deElhuyar of Spain first prepared metallic tungsten from wolframite. They derived an acid from wolframite which was similar to acid obtained by Scheele from tungsten (scheelite), and succeeded in producing a new metal by reduction of this acid with charcoal. Also, they determined that the mineral wolframite contained iron and manganese. The metal took over the old name of its mineral tungsten. Also the metal is known as wolfram, derived from the name of its other mineral, wolframite. The word wolfram originated from the wolf-like nature of the mineral that it devoured tin during the tin smelting operation causing low recoveries. The element was given the symbol W for its old name wolfram.
Tungsten is widely distributed in nature, occurring in several minerals. It is found in scheelite, CaWO4; wolframite, (Fe,Mn)WO4; huebnerite, MnWO4; ferberite, FeWO4; tungstite, H2WO4; and cuprotungstite, CuWO4. Its abundance in the earth’s crust is estimated to be 1.25 mg/kg and average concentration in seawater is about 0.1 μg/L.

Production

Tungsten is recovered mostly from mineral scheelite and wolframite. The recovery process depends on the mineral, the cost, and the end use; i.e., the commercial products to be made. Typical industrial processes have been developed to convert tungsten ores to tungsten metal and alloy products, tungsten steel, non-ferrous alloys, cast and cemented tungsten carbides, and tungsten compounds. A few processes are mentioned briefly below.
The first step in recovery is opening the ore. If the ore is scheelite, CaWO4, it is digested with hydrochloric acid:
CaWO4 + 2HCl → H2WO4 + CaCl2
Tungstic acid, H2WO4 precipitates out. The precipitate is washed and dissolved in sodium or ammonium hydroxide solution during heating:
H2WO4 + 2NaOH → Na2WO4 + 2H2O
Sodium tungstate is crystallized, separated from any impurities in the solution, and digested again with hydrochloric acid to form tungstic acid in purified form. The pure acid is dried, ignited and reduced with carbon to form tungsten powder from which most non-ferrous alloys are made.

Uses

To increase hardness, toughness, elasticity, and tensile strength of steel; manufacture of alloys; manufacture of filaments for incandescent lamps and in electron tubes; in contact points for automotive, telegraph, radio and television apparatus; in phonograph needles. Tungsten carbides (W2C, WC) used in rock drills, metal-cutting tools, wire-drawing dies. WC used as catalyst instead of platinum: Bennett et al., Science 184, 563 (1974).
InChI:InChI=1/W

7440-33-7 Well-known Company Product Price

Brand (Code)Product description CAS number Packaging Price Detail
Aldrich (767522)  Tungsten  sputtering target, diam. × thickness 2.00 in. × 0.25 in., 99.95% trace metals basis 7440-33-7 767522-1EA 5,494.32CNY Detail
Aldrich (356972)  Tungsten  wire, diam. 0.5 mm, ≥99.9% trace metals basis 7440-33-7 356972-18.9G 1,213.29CNY Detail
Aldrich (267554)  Tungsten  wire, diam. 0.25 mm, ≥99.9% trace metals basis 7440-33-7 267554-9.5G 670.41CNY Detail
Aldrich (267562)  Tungsten  wire, diam. 1.0 mm, 99.99% trace metals basis 7440-33-7 267562-15G 824.85CNY Detail
Aldrich (276324)  Tungsten  rod, diam. 4.0 mm, 99.99% trace metals basis 7440-33-7 276324-24G 1,404.00CNY Detail
Aldrich (510106)  Tungsten  powder (monocrystalline), 0.6-1 μm, ≥99.9% trace metals basis 7440-33-7 510106-500G 1,423.89CNY Detail
Aldrich (357421)  Tungsten  powder, 10 μm, ≥99.99% trace metals basis 7440-33-7 357421-10G 1,062.36CNY Detail
Aldrich (267511)  Tungsten  powder, 12 μm, 99.9% trace metals basis 7440-33-7 267511-500G 2,197.26CNY Detail
Aldrich (267511)  Tungsten  powder, 12 μm, 99.9% trace metals basis 7440-33-7 267511-100G 572.13CNY Detail
Aldrich (267538)  Tungsten  foil, thickness 0.05 mm, ≥99.9% trace metals basis 7440-33-7 267538-2.4G 580.32CNY Detail
Aldrich (357197)  Tungsten  foil, thickness 0.127 mm, ≥99.9% trace metals basis 7440-33-7 357197-100CM2 2,936.70CNY Detail
Aldrich (357197)  Tungsten  foil, thickness 0.127 mm, ≥99.9% trace metals basis 7440-33-7 357197-6G 873.99CNY Detail

7440-33-7SDS

SAFETY DATA SHEETS

According to Globally Harmonized System of Classification and Labelling of Chemicals (GHS) - Sixth revised edition

Version: 1.0

Creation Date: Aug 16, 2017

Revision Date: Aug 16, 2017

1.Identification

1.1 GHS Product identifier

Product name tungsten atom

1.2 Other means of identification

Product number -
Other names Tungsten ICPStd.

1.3 Recommended use of the chemical and restrictions on use

Identified uses For industry use only.
Uses advised against no data available

1.4 Supplier's details

1.5 Emergency phone number

Emergency phone number -
Service hours Monday to Friday, 9am-5pm (Standard time zone: UTC/GMT +8 hours).

More Details:7440-33-7 SDS

Please post your buying leads,so that our qualified suppliers will soon contact you!

*Required Fields