Boron carbide, also known as black diamond, is an inorganic substance with a chemical formula of B4C, usually a gray-black micropowder. It is one of the three hardest known materials (after diamond and cubic boron nitride) and is used in tank armor, body armor and many industrial applications.

Several preparation methods of nano-boron carbide (supply 100-200nm):

1. Carbothermal reduction method

Because of its low density, high strength, high temperature stability and good chemical stability. It is used in wear-resistant materials, ceramic reinforced phases, especially in lightweight armor, reactor neutron absorbers, etc. In addition, compared with diamond and cubic boron nitride, boron carbide is easy to manufacture and low in cost, so it is more widely used. It can replace expensive diamond in some places and is commonly used in grinding, grinding, drilling and other applications.

2. Self-propagating high temperature synthesis method

Self-propagating high temperature synthesis, also often referred to as SHS technology. This method was invented by Merzhahov of the former Soviet Institute of Physical Chemistry. This method has the advantages of low reaction temperature (1000 ℃ ~ 1200 ℃), energy saving (after using external energy to ignite, the combustion wave can be carried out only by the heat released by the reaction), rapid reaction, etc., so the synthesized boron carbide The purity of the powder is high and the particle size of the original powder is relatively fine (0.1-4μm), and generally does not need to be broken again. In addition, during the SHS process, the heating and cooling rates are extremely fast, and it is easy to form high-concentration defects and non-equilibrium structures. The crystal shape of the powder is irregular, which can make the product have high activity and improve its sintering performance. However, it is extremely difficult to thoroughly wash off the boron and magnesium impurities in the product, which will increase the process flow and cost, which is a problem that should be further studied in the process.

3. Polymer precursor cracking method

The low-temperature precursor cracking method is a method in which inorganic substances or metal alkoxides undergo four processes of solution, sol, gel, and solidification, and then undergo heat treatment to become solid compounds. The method can design and control the uniformity and particle size of boron carbide powder at the molecular level, so as to obtain ultra-fine, high-purity and uniform nanomaterials. The carbon source is generally glycerol, citric acid, polyvinyl alcohol, glucose, mannitol, starch, sucrose and cellulose, etc., and the boron source is boric acid or boron anhydride.

4. Sol-gel method

The basic principle of this method is that easily hydrolyzed metal compounds (inorganic salts or metal alkoxides) react with water in a solvent, gradually gelatinize through hydrolysis and polycondensation, and then undergo drying and sintering to obtain the desired materials. The basic reactions include hydrolysis reaction and polymerization reaction, which can prepare single-multi-component mixture with high purity, uniform particle size distribution and high chemical activity at low temperature.

Selecting suitable boron source and carbon source to form gel, this method has the advantages of more uniform molecular-level mixing of raw materials, low reaction temperature, and bulky product.

SAT NANO is professional manufacturer of B4C boron carbide powder, we can supply nano particle and micron particle, if you have any enquiry, please feel free to contact us at admin@satnano.com