Titanium (Ti) is a silver-gray metal, a structural metal with light weight, high strength and corrosion resistance, and its alloy is used to manufacture parts of high-speed aircraft. In 2008+079 1 year, the British chemist and mineralogist W. Gregor discovered the compound of titanium and oxygen. 1795, German chemist M.H. klaproth also independently discovered this compound and named it. Titanium is widely distributed, accounting for 0.44% in the crust. In fact, all rocks, sandstone, clay and other soils contain titanium compounds. Two important industrial minerals of titanium are ilmenite and rutile. 19 10 metallurgist M.A. Henry reduced titanium tetrachloride (TiCl4) with sodium in a closed steel cylinder to produce pure titanium. 1950, industrial production of titanium by Kroll method (reduction of titanium tetrachloride with magnesium). The specific gravity is about half that of iron and less than twice that of aluminum; It can be polished to a high finish. Titanium has low electrical conductivity and thermal conductivity, and is a paramagnetic material (slightly attracted by magnets). Titanium has two crystal structures: hexagonal close-packed structure (α) below 883℃; When the temperature is higher than 883℃, it has a body-centered cubic structure (β).
Natural titanium consists of five stable isotopes: 46(8.0%), 47(7.3%), 48(73.8%), 49(5.5%) and 50(5.4%). Titanium is very important because it can form alloys with most metals and some nonmetals. The tensile strength of some titanium alloys is much higher than that of titanium itself. Therefore, it has excellent corrosion resistance in many occasions. Even if titanium is immersed in seawater for more than 3 years, there will be no obvious corrosion. Titanium has the advantages of high strength, low specific gravity and excellent corrosion resistance, so it can be used to manufacture various parts of airplanes, spaceships and ships. Titanium does not react with muscle tissue and bone, so it can be used as plastic surgery material. Titanium has been used as deoxidizer in steelmaking, and can be used as alloy additive in various steels to reduce its carbon content. Used in aluminum to increase its crystal size; Used in copper to improve its hardness. Although titanium is not easy to lose its luster at room temperature, it can react with oxygen in the air at high temperature. In the forging or processing of titanium alloy, this oxidation reaction does not damage the superior properties of titanium, and the oxide layer can be removed after processing. However, titanium is very active in liquid state and can reduce all known refractories.
What is an alloy?
The so-called alloy is a metal material composed of two or more elements, which exists in the form of compounds or solutions. The main element composition is generally metal, but nonmetallic carbon is an important component of steel. Alloys are usually made by melting a mixture of their components. The value of alloys was discovered in ancient times, especially brass (copper-zinc alloy) and bronze (copper-tin alloy). The most important thing now is alloy steel. Generally speaking, alloy steel contains quite a few other elements besides iron and carbon.
Manganese, molybdenum, silicon, tungsten, vanadium and boron. Alloy steel has a wide range of special properties, such as hardness, toughness, corrosion resistance, magnetization and ductility. Some non-ferrous alloys (mainly copper-nickel alloy, bronze and aluminum alloy) are widely used to make coins. Sometimes it is difficult to distinguish between alloying elements and impurities. For example, in aluminum alloys, silicon can be considered as an impurity or a useful component according to its use, because silicon can improve quality.
(232℃) alloy. Most of these alloys are mixtures of low melting point metals such as tin, bismuth and lead. Fusible alloy is used as solder. Used as a safety piece in fire extinguishing device, when the heat of flame melts the alloy, it will automatically spray water; It is also used as a fuse. When the current is overloaded, it will melt and cut the circuit. Many fusible alloy formulations melt at 90 ~ 100℃, for example, Dusit fusible alloy (50% bismuth, 25% lead, 25% tin) melts at 98℃. In this fusible gold, half of tin is replaced by cadmium to form a wood alloy with a melting point of only 70℃. There is indeed a manganese titanium alloy!
The author consulted some authoritative documents, including the Encyclopedia Britannica.
International Chinese Edition), Academic American Encyclopedia, China Encyclopedia,
Encyclopedia of materials science and technology, metal handbook and China Material Engineering Grand Ceremony, etc. , in these currents.
There is no description of manganese-titanium alloy in the valid version of the data.
Whether it is an international standard (ISO) through the Shanghai Standardization Service Information Network and the website of the National Standardization Administration Committee;
Foreign standards such as American National Standard (ANSI), American Society for Testing and Materials (ASTM), British National Standard (BS),
German national standard (DIN), French national standard (NF) and Japanese industrial standard (JIS); Or Chinese national standard (GB)
China hasn't established the standard of manganese-titanium alloy.
Further searching the relevant literature and publications, it was found that there were foreign scholars' literature reports on the basic research work of Mn-Ti alloy. Manganese-titanium alloy is a binary alloy, which was involved in the alloy database of National Physical Laboratory (NPL) (March 2000). The alloy Mn/Ti 87.5/ 12.5 (atomic percentage) was prepared by ACI Alloy Company in San Jose, USA.
Manganese-titanium alloy Mn/Ti 88/ 12(at%) has better corrosion resistance than manganese in alkaline solution containing chloride ions (Corrosion Science, 1997, Volume 39, pages 305-320) because a protective film is formed on its surface. Experts from the United States Naval Research Laboratory have also studied this.
(Journal of American Electrochemical Society, 2004, vol. 15 1, No.2, p.2) B82-B89).
As a new alloy material, Mn-Ti alloy is still in the basic research stage, and its special properties and application fields are being explored. The practical application of Mn-Ti alloy will take some time.