Basic Properties, Synthesis and Typical Properties of Boron Carbide

If you are looking for high-quality products, please feel free to contact us and send an inquiry, email: brad@ihpa.net



What is Boron Carbide?

Boron Carbide Powder belongs to the trigonal system. The unit cell contains 12 B and 3 C. The unit cell’s stereo diagonally connected C atoms are in an active configuration. They can be substituted by B atoms, forming a replacement solid and leaving the crystal lattice in order to form high-boron compounds.

B4C’s molecular weight is 52.25 and it has C21.74% & B78.25%. The color is usually gray or black. It has a density of 2.51g/cm3, the Mohs Hardness is 9.35, and the microhardness is 49GPa.


B4C Powder has a melting temperature of 2450°C (decomposition). The coefficient for expansion at 1000degC (4.5×10-6degC-1) is 4.5×10-6degC-1. Thermal conductivity is 121.4W/m*k for 100degC, and 62.79W/m*k for 700degC. B4C powder can be used primarily as an abrasive. B4C hot-pressed products are suitable for wear-resistant or heat-resistant parts. B4C has a wide range of applications in the refractory and refractory industries. It is often used as a refractory additive, for example to add antioxidants to carbon-bonded refractories. Unshaped materials enhance the strength and resistance to corrosion of the body.

The properties and synthesis of Boron Carbide

B4C powder is commonly synthesized by reducing boron anhydride and excess carbon.

2B2O3+7C-B4+6CO|


The synthesis reaction may be performed in an electric arc or muffle furnace. In a resistance-type furnace, the best way to synthesize B4C is by heating boron anhydride B2O3 with carbon C until it reaches a lower decomposition temperature than B4C. B4C is broken down into boron and carbon rich phase in an electric-arc furnace because of the high temperature. The reaction product may contain a lot of free C (20%-30%). As a result, the B4C obtained is of slightly inferior quality.


In order to synthesize B4C using an electric arc, boric acids (with a content greater than 92%), artificial graphite with a fixed carbon of greater than 95%, and petroleum coke with a fixed carbon greater that 85% are used. The theoretical dosage is calculated based on the reaction formula. The theoretical amount is approximately 2% higher. Each of artificial graphite and petroleum coke accounts for 50% of total carbon addition, which is then 3%-4% more than the theoretical amount. Add the three prepared raw materials to a ball-mill and then add them to the arc. B4C can be produced by reducing and Carbonizing the furnace from 1700-2300. Finaly, the frit will be sorted and cleaned, then crushed, ground, picked, sedimented and classified, etc. to produce B4C in various particle sizes.


(aka. Technology Co. Ltd., a trusted global chemical materials supplier & manufacturer has over 12 years experience in providing high-quality nanomaterials and chemicals. The B4C powder that we produce is of high purity with a fine particle size. If you need lower, please call us.