Tin metal
Tin (Sn) is one of the few metals that has been used and traded by humans for more than 5000 years. From back in history, it has been used in combination with copper to make bronze. Copper was first coated with tin in the first century AD and tin-plated iron was manufactured as early as the 16th century. Tin has interesting properties : a low melting point, malleability, resistance to corrosion and fatigue, as well as the ability to alloy easily with other metals. It is also non-toxic and easy to recycle.
Cassiterite (SnO2) is by far the most important tin ore, although small amounts of tin are recovered from sulphide minerals such as stannite (Cu2FeSnS4). Tin is extracted by roasting cassiterite in a furnace with carbon. Though a very common metal, tin makes up only about 0.001% of the earth’s crust.
Tin usage
Tin is an important commodity in international trade. Throughout the world, it is used in hundreds of industrial processes and products, such as food packaging, culinary equipment, electronics, tin chemicals, plumbing solders, engineering alloys, pewter and bronze in music and arts, dental amalgams, anti-corrosion and engineering coatings, wine capsules and fire retardants.
Tin resists corrosion and acts as a protective coating on other metals. It is added to glass to produce automotive glass and window glass. Tin is also part of many useful alloys : bronze is an alloy of tin and copper; tin and lead are alloyed to make pewter and solder; an alloy of tin and niobium is used to make superconductive wire. Tin salts may also be sprayed onto glass. Tin is used as plating to avoid corrosion of various metals.
Tin world market
Tin, together with copper, were the first metals to be traded at LME (London Metal Exchange) in 1877.
After the closing of several tin mines in Indonesia, world annual production of tin went down from 2005 to 2007 from 348,500 tons to 337,000 tons, thus creating a deficit of 30,700 tons per year. The five top producers of tin are China, Indonesia, Peru, Bolivia and Brazil produce more than 90% of the world production, yet they cannot cope with the deficit which is foreseen to increase in the coming years.
Tin consumption is expected to increase to 386,000 tonnes next year and to 398,000 tonnes in 2008.
The average price of tin jumped up in one year from $8,774 per tonne at mid 2006 to $13,080 per tonne at mid 2007. Recently, it has reached $17,000 per tonne.
The growth rate of tin usage in the world for 2006 was 18.6 %. In Asia only, tin usage increased by 27 %, and in China, by 34 %. This increase is due to the gradual implementation of the lead-free soldering regulations, but also to the general increase of electronic device production throughout the world.
Tantalum metal
Tantalum is a rare, non-radioactive metal. In nature, tantalum (Ta) is almost always found in oxide form together with niobium (also known as columbium) . The principal source for tantalum is the mineral columbite-tantalite found in Australia, Brazil, Canada and Democratic Republic of Congo, with lesser quantities originating from Southeast Asia. The tantalum content of the ore found on DRC and neighbouring countries is recognized as being uniquely high.
In its refined forms, tantalum is grey, heavy and very hard. It is so ductile that it can be drawn into very fine wires. It is used to make a variety of super alloys with desirable properties such as high melting point, high strength and ductility. At high temperatures, tantalum becomes much more reactive. It has a melting point exceeded only by tungsten and rhenium. Scientists at Los Alamos laboratory in the USA have produced a tantalum carbide graphite composite material, which is said to be one of the hardest materials ever made with a melting point of 3738oC. Tantalum is almost completely immune to chemical attack at temperatures below 150oC, and is attacked only by hydrofluoric acid, acidic solutions containing the fluoride ion, and free sulphur trioxide.
Tantalum usage
60% of its commercial use is in the field of consumer electronics, such as cellular phones, DVD players, computers, gaming platforms, specialty electronics, where it is used for its capacity to store and release electrical charges.
Tantalum is also widely used in surgical applications, as it is immune to body liquids and is non irritating, and in the fabrication of chemical process equipment, nuclear reactor components, copper wire coating, furnace parts, anodes in cathode protection, heat exchangers, turbines for aircraft and electrical generation and camera lenses, as tantalum oxide films are stable and have good refractive and dielectric (anti-static) properties.
Tantalum world market
Tantalum is not traded on any metal exchange market. It is mainly sold on long-term supply contracts, which are not publicly disclosed.
We are lacking reliable figures on the world tantalite production and the world tantalum consumption. Yet official figures state that the main producer is by far Australia, which « officially » supply 60% of the world tantalum metal produced from ore (that is to say excluding the recycling of tantalum components).
The world tantalum processing industry is also highly concentrated. Very few companies are involved in it : the US CABOT and its numerous subsidiaries, the German H. C. STARCK, two Kazakh companies, BELOGORSKY and IRTYSH, and a few Chinese companies controlling medium-sized processing plants.
Tantalum is critical to the global electronics industry because it offers the design engineer high capacitance in a small case size.
Pricing for raw material has remained steady, while materials pricing for tantalum have been more readily influenced by changes in the high-tech economy.
Driven by the acceleration of miniaturization in electronics, the average yearly growth rate of tantalum consumption is reported to be about 5% to 8%. This growth has caused a significant increase in exploration.
Niobium metal
Columbium and niobium are synonymous. The chemical element niobium (Nb) with atomic number 41 was the name given the name Columbium in 1801, and niobium was the name officially designated by the International Union of Pure and Applied Chemistry in 1950.
Niobium usage
Niobium is added to steel and stainless steel to create high strength low alloy steel. It doubles the strength and toughness of steel due to grain refining while reducing weight. Therefore ferro-niobium alloy is being used in oil and gas pipelines, chemical processing equipment, car and truck bodies, architectural steel, tool steels, ships’ hull, railroad tracks, nuclear reactors (niobium-based steel keeps the reactor safe) or cutting tools in machining operation are fabricated from niobium carbide (to avoid high temperature deformation).
Superconducting magnets are fabricated from niobium-titanium/tin alloy: a magnet made with an alloy of niobium and tin proves to be three (3) times stronger than the next best magnet made without niobium. Niobium based magnets are used in medical magnetic resonance imaging (MRI) equipment, magnetic levitation high speed train (in Japan) or particle physics experiments.
Niobium-nickel-ferro alloys, because of high temperature resistance, improved creep, corrosion and oxidation resistance, are used for the manufacture of turbine blades of jet aircraft, turbine blades of electric power plants, high temperature and pressure tubing of heat exchangers and boilers, etc … for the refineries and power plants.
Niobium oxide, because of its high index of refraction, high dielectric constant and increase in the light transmittance is used for camera lenses, coating on glass for computer and TV screens or high quality scratch resistance thin-eye glasses and resistant watch glass.
Because of high dielectric constant and stability, niobium powder has been recently used to manufacture capacitors for the electronic industry.
Now niobium alloys are also becoming more popular in the manufacture of high quality jewellery, because of their lightweight and hypoallergenic characteristic.
Niobium world market
Main reserves of niobium are known to be located in Brazil and Canada, but countries like China, Australia, and of course Central African countries hold reserves that still need to be fully assessed and exploited.
In the same way, Brazil and Canada are by far the two main producers of niobium in the world, but some new players are coming up on this emerging market.
Demand of niobium ferroalloys in steelmaking increased about 19% compared with that of 2005; niobium demand in super alloys (mostly for aircraft engine components) decreased about 2% compared with that of 2005, and overall apparent consumption rose about 38%.
Tungsten metal
Tungsten was discovered by two Spanish chemists in samples of the mineral wolframite in 1783. Today, tungsten is still primarily obtained from wolframite - (Fe, Mn) WO4 - and scheelite - CaWO4). Tungsten ores are processed with alkalis to form tungsten trioxide (WO3) and then heated with carbon or hydrogen gas to form tungsten metal.
Tungsten usage
Because tungsten has the highest melting point of all metallic elements, it is used to make filaments for incandescent light bulbs, fluorescent bulbs and television bulbs. Because tungsten expands at nearly the same rate as borosilicate glass, it is used to make metal to glass seals. Because tungsten is extremely stable at high temperatures, it is used to make target for X-ray production, heating elements in electric furnaces, parts of spacecraft and missiles, high-speed cutting tools or rocket engine nozzles.
Combined with carbon in tungsten carbide (WC), it becomes a very hard compound, used for tips of drill bits, high-speed cutting tools or mining machinery. Combined with disulfide, it is a dry lubricant that can be used to temperatures as high as 500ºC. Combined with calcium and magnesium, it is used in fluorescent light bulbs.
Tungsten world market
China is by far the most important producer of tungsten in the world, and the country that hold the largest resources. Canada and Russia are also playing a major role on the production side. Whereas the United States with a significant assessed reserve of tungsten still need to import most of the material they process.
Tungsten prices are remained steady until 2002, when they suddenly increased from $5,000 per metric ton to over $ 25,000 at mid-2005.
|
