Product name: High Purity Lanthanum Metal

Chemical formula: La

CAS: 7439-91-0

EINECS: 231-099-0

Purity: 99.9%

Color: silver white

Atomic weight: 138.9

Atomic number: 57

Melting point: 920°C

Boiling point: 3464°C

Density: 6.162g/cm3

Production standards: GB/T 15677-2010

Shape: block, powder, sheet, wire, rod, foil or according to customer's requirements

Packaging: packed in iron drum, lined with single/double plastic bags and filled with argon for protection or according to customer's requirements

 

 

The content of lanthanum in the earth's crust is 0.00183%, and its content among rare earth elements is second only to cerium. Lanthanum has two naturally occurring isotopes: lanthanum-139 and radioactive lanthanum-138. Lanthanum is found in monazite sand and bastnaite.

 

 

Lanthanum is the first element of the lanthanide series. It is a silver-white metal that is soft and easy to cut. It exists stably under normal temperature and pressure. It has certain ductility, plasticity and conductivity, and can resist corrosion well. Metal lanthanum has active chemical properties and is easily soluble in dilute acid. It is easy to oxidize in the air, and the fresh surface will darken quickly when exposed to air. When heated, it burns, forming oxides and nitrides. It is heated in hydrogen to form hydride, corrodes slowly in cold water, and reacts strongly in hot water to release hydrogen. Lanthanum can react directly with carbon, nitrogen, boron, selenium, silicon, phosphorus, sulfur, halogen, etc. Lanthanum compounds are diamagnetic. High-purity lanthanum oxide can be used to manufacture precision lenses. Lanthanum-nickel alloys can be used as hydrogen storage materials. Lanthanum hexaboride is widely used as high-power electron emission cathodes.

 

 

Lanthanum is generally prepared by dehydrating hydrated lanthanum chloride and reducing it with metallic calcium, or by electrolyzing anhydrous lanthanum chloride after melting.

 

 

Lanthanum is widely used in piezoelectric materials, electrothermal materials, thermoelectric materials, magnetoresistive materials, luminescent materials, hydrogen storage materials, optical glass, laser materials, various alloy materials, etc. Lanthanum is also used in catalysts for the preparation of many organic chemical products. Lanthanum is also used in light-converting agricultural films.

 

1.Steel modifier

Metal lanthanum or mixed rare earth metals can be added to steel to desulfurize and oxygenate, refine grains, form microalloys, change the shape and distribution of inclusions, reduce the hydrogen diffusion coefficient, and improve resistance to hydrogen embrittlement and stress corrosion; adding to iron can purify molten iron, change the shape of graphite and prevent impurity elements from destroying the spheroidization effect. Since steel is widely used in various fields, lanthanum metal plays an important role in the development of high-performance products such as steel and cast iron.

 

2.Reducing agent

Metallic lanthanum and cerium have similar properties. Lanthanum chips and samarium oxide are mixed and pressed into briquettes. A reduction reaction occurs at high temperatures. The difference in vapor pressure can be used to separate and purify by vacuum distillation to obtain high vapor pressure metals such as samarium. The equipment for this process is vacuum induction furnace or vacuum resistance furnace, the reduction and distillation processes are carried out at the same time, the process is simple and there is less pollution.

 

3. Metal square rod lining

Due to their active chemical properties, pure rare earth metals can easily react with oxygen, sulfur, and nitrogen to form stable compounds. When sparks are generated by severe friction and impact, they can ignite flammable materials. Therefore, it was made into flint as early as 1908. It has been found that six of the 17 rare earth elements, cerium, lanthanum, neodymium, praseodymium, samarium and yttrium, have particularly good arson properties. Lanthanum has the lowest price. People have used the pyrophoric properties of rare earth metals to create various incendiary weapons. For example, the U.S. Mark-82 227kg aerial bomb is lined with rare earth metals. In addition to producing explosive killing effects, it also produces arson effects. The U.S. air-to-ground "Damperman" rocket warhead is equipped with 108 rare earth metal square rods as linings to replace some prefabricated fragments. Static blasting tests have proven that its ability to ignite aviation fuel is 44% higher than that without linings.

 

4. Lanthanum metal foil

Metal lanthanum wire can absorb harmful gases such as oxygen, nitrogen, carbon monoxide, carbon dioxide and water vapor released by the electron tube electrode due to bombardment and thermal diffusion, thereby maintaining a high vacuum in the electron tube. Various rare earth metal and alloy foils have large neutron absorption areas and can effectively capture neutrons. Metal lanthanum wire and foil are widely used in electronics, lighting, nuclear industry and other fields.

 

5. Pyrogenic alloy

Mixed rare earth metals (RE, containing La25%) and Fe were used to make a variety of pyrophoric alloys earlier in China, which can be divided into two types: military and civilian. Military pyrophoric alloy is made of RE60-80% (including La25%), Fe20-40% and a small amount of Al, Ca, Si and C. It is mainly used to make fuses and ignition devices for bullets, shells and bombs,etc. Civilian pyrophoric alloys are made of RE75-80% (including La25%), Fe15-18% and a small amount of Mg, Zn, Cu, Al, etc., with a ignition rate of ≥85%. They are mainly used for flints in lighters and various toys' firestones, etc. In addition, pyrophoric alloys are also used in industrial gas lamps, welding gun igniters and torch igniters.

 

7.Lanthanum metal target

Lanthanum targets are mainly used in coating, polishing and other fields. There is a radioactivity problem when using thorium-tungsten material for the hot electron cathode, but this problem does not exist for the lanthanum-molybdenum cathode. Its emission performance largely depends on the active material layer on the surface of the material. Hao Shiming et al. used molybdenum as the matrix and lanthanum as the target material, and used pulse laser technology to prepare a uniformly distributed lanthanum oxygen film, and obtained a lanthanum-molybdenum cathode with excellent performance. CVD diamond film has good thermal conductivity and light transmittance and is widely used. However, the surface grain and roughness of the film are large and the performance is low. Surface polishing is achieved by utilizing the reaction and diffusion of carbon elements and rare earth metals on the diamond surface, which can speed up the polishing speed and improve the precision of the diamond film. The high-purity lanthanum target has fewer impurities and vacancies, the structure of the sputtering film layer is more uniform, and the performance is more stable.

 

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