Indium — fusible, very soft and ductile silvery sheen of the metal. 49-th element of the fifth period table of chemical elements where symbol In (Indium),. In its qualities it is close to aluminum and gallium, in appearance to zinc. The name comes from the shade of spectral lines inherent in India — Indigo.
|Atomic number||Atomic (molar) mass, g/mol||The degree of oxidation||Density [g/cm3]||The melting temperature t°C||The boiling point of t°C||The heat of fusion kJ/kg|
|No. 49||114,8||1, 3||7,362||256°C||2072°C||3,24|
In 1863, the German scientists Reich and Richter in the spectral study of zinc blende got in the line spectrum of Indigo. Scientists have searched for gallium, which gives a spectral line is green, but instead discovered a new element. Isolated in pure form, indium has proved to be very plastic — much softer lead, is 20 times softer than gold. Tiny ingot new metal in the form of a pencil about one hundred grams of the French Academy of Sciences was estimated at 80 thousand dollars. Four years later the universal exhibition of 1867 indium was presented polukilogrammovy ingot. Today, the cost of this metal about $ 700 per kg. World consumption of indium is growing every year. In 2010 it reached 900 tons.
Indium in the form of trace impurities found in a number of minerals. Its high Fe content in sphalerite — a few grams per kilogram, chalcopyrite and stanine — ten times less, and in cassiterite and pyrrhotite is even less, as well as in pyrite, arsenopyrite, wolframite — grams per tonne. The total content of indium in the earth’s crust at approximately 0.25 g/t In sea water it is even more — 18 g/t
It is believed that chemistry is not useless waste. Proof of this is the technology of obtaining of indium from waste. The very history of its discovery is associated with ore under the name «zinc blende». Currently, indium is obtained from intermediate waste in the production of zinc, tin, copper, and lead. Although there indium is contained in minute amounts — up to 0.1%, and separation from accompanying elements — cadmium, zinc, copper, antimony and other — a rather difficult task, but worth it: indium is needed. In the first stage of concentration is its separation from copper, zinc and cadmium. The raw material is treated with sulfuric acid, which dissolves the metals, and hydrolytic deposition of isolated concentrate. This is achieved by changing the acidity of the solution. Cadmium hydroxide is precipitated at a pH of about 8, zinc hydroxide and copper — 6. To «plant» the India hydroxide, the pH of the solution is required to bring to 4. From concentrate «rough indium» is recovered by cementation on zinc and aluminum. «Clean India» is produced by refining using the zone melting.
Oil purity classes
On the territory of the former Soviet Union from January 1, 1997, acts of the interstate standard GOST 10 297−94 regulating the quality produced by India bullion pyramids and bars. According to the standard of the metal is five cleanliness classes, depending on the percentage content of the element. So mark Ин0000 contains this element in an amount of 99.9999 percent. In Ин000 the share of clean India of 99.9995%. In Ин00 Is 99.999%. Ин0 has a chemical purity of 99,998%. And the brand Ин2 — of 99.97%.
The density of India at 20 °C is 7,362 g/cm3. If the magnesium ignites at 623 °C, indium withstands heat up to 800 °C, and then breaks out a violet-blue flame with formation of oxide. This metal is insoluble in almost all acids, in inorganic (especially easy in perchloric and nitric). Resistant to alkalis but react with bromine and chlorine, and when heated with iodine, sulphur, phosphorus pairs. Critical temperature of superconductivity, India = 3,405°To
- As the acceptor additive silicon and Germany in microelectronics.
- For low-melting solders. India exceptional adhesion to many materials allows soldering, for example, metal with glass.
- In the manufacture of glass for LCD monitors.
- Coating indium mirrors and car headlights gives the reflectivity at the silver level, and resistance to atmospheric influences is higher.
- For the calibration of thermocouples.
- For photovoltaic cells.
- As the phosphor.
- Coating indium aluminum diesel piston skirts reduces wear.
- Indium arsenide is a high — temperature high-performance thermoelectric, to increase the efficiency even legarrette 10% of indium phosphide.
- The isotopes 111In and 113In used in radioisotope diagnosis.
- The indium isotope 115In — for the detection of neutrinos with a threshold energy of 120 Kev: 115In + ν e → 115Sn+e-+2γ
- Indium is part of the «blue gold».
In the XXI century the consumption of indium in the world is rapidly growing and in 2009 reached 900 tons. It is indispensable in the technique of high vacuum seals (gaskets, coatings); in particular, when sealing the space vehicles and particle accelerators. Electrochemical system of indium-mercury oxide is used to create batteries of high specific energy consumption. The alloy of indium with silver is resistant to hydrogen sulfide and is used to create a high-quality reflective coatings. Its alloys with gallium, tin and zinc will melt at room temperature and can be liquid-metal coolants. Indium absorbs thermal neutrons and can be used to control the nuclear reaction. Even better in this role — its compounds with other elements, exciting neutrons. Indium oxide produced glass that absorbs thermal neutrons. The most famous composition of the glass — indium oxide (12%),.boron oxide (33%), cadmium oxide (55%). Indium having a low melting point is essential in the production of liquid crystal displays and as a component of low-melting solders and alloys. Orthophosphate India included in dental cements
Indium bring a covered transport. Rail transport party based on one recipient 1 package. Brand Ин000 and Ин00 is transported in the form of ingots or pyramids with weight from 50 grams to 1 kg. For other brands weighing up to 3 kg. If necessary, the ingots Ин000 can weigh 20 to 50 grams, and elongated by Czochralski method — weighing up to 2.5 kg. Brand Ин00 supply rods Ø 21−25 mm and length 50 — 70 mm or Ø 22−24 mm and a length of 63 — 67 mm.
On the surface of samples allowable minor defects, does not extend beyond the specified standard. Each ingot is marked. Bullion India Ин000 and Ин0000 each packaged separately in plastic wrap Bullion Ин00 and Ин0 can pack in pairs. Ин2 bars are Packed either in plastic wrap or waxed paper.
Buy at best price
In stock, LLC «Electrocentury-steel» a wide range of hire of the rare metals. Supplied products from India at reasonable prices. The technical documentation of products includes data on the chemical composition, limiting the percentage of impurities; mechanical qualities of products; quality of the surface. Attached are the results of ultrasonic inspection. The timing of orders is minimal. For wholesale customers a preferential discount.