Berat KAPAR, BSc. Student

Metallurgical and Materials Engineering

Yıldız Technical University

 

beratkapar99@gmail.com

www.linkedin.com/in/ beratkapar/

 

Low Cost Synthesis of Boron Carbide

Co-Supervisors: Oğuz Karaahmet, Yasin Bozkurt Yılmaz

Boron carbide is characterized by a unique combination of properties, such as, high melting point (2447 °C), high hardness (28–35 GPa Knoop hardness), low density (2.52×103 kg/m3), high Young's modulus (450–470 GPa), high corrosion and oxidation resistance[1]. This properties make it a material of choice for a wide range of engineering applications. Boron carbide is used in refractory applications due to its high melting point and thermal stability; it is used as abrasive powders and coatings due to its extreme abrasion resistance; it excels in ballistic performance due to its high hardness and low density; and it is commonly used in nuclear applications as neutron radiation absorbent. In addition, boron carbide is a high temperature semiconductor that can potentially be used for novel electronic applications. [2] There are several methods for boron carbide production such as; carbothermal reduction[3], synthesis from elements[4], magnesiothermic reduction[5], chemical vapor decomposition[6], synthesis from polymer precursors. Carbothermic reduction process is an economic method to produce boron carbide powder. This method is utilized to produce a boron carbide powder using commercial purity raw materials. Boron oxide as a source of boron, and carbon active as reducing agents is used. Mixtures of boron oxide and carbon bearing material is placed in a graphite crucible and heated under a flow of argon atmosphere in a tube furnace to 1400–1550 °C [7]. This result in the formation of boron carbide powder with or without un-reacted starting raw materials. Our study is aimed to produce low-cost, high purity boron carbide. To achieve this, we try various methods such as condensing precursor powders, using catalysts, low temperature synthesis to save energy.

 

[1] “Boron carbide-A comprehensive review” Thévenot, F. Journal of the European Ceramic Society Volume 6, Issue 4, 1990, Pages 205-225

[2] K.A. Schwetz, L.S. Sigl, L. Pfau “Mechanical Properties of Injection Molded B4C-C Ceramics” J. Solid State Chem., 133 (1997), p. 68

[3] G. Goller, C. Toy, A. Tekin and C. K. Gupta: ‘The production of boron carbide by carbothermic reduction’, High Temp. Mater. Proc., 1996, 15, (1–2), 117–122.

[4] A. W. Weimer: ‘Carbide, nitride and boride materials, synthesis and processing’, 89–95; 1997, London, Chapman & Hall.

[5] T. A. Zhang Z. H. Dou, H. Yang and Q. L. Ding: ‘Preparation of boron carbide by magnesium reducing – SHS’, J. North Eastern Univ., 2003, 24, (10) 935–938.

[6] B. Zeng, Z. Feng, S. Li, Y. Liu, L. Cheng and L. Zhang: ‘Microstructure and deposition mechanism of CVD amorphous boron carbide coatings deposited on SiC substrates at low temperature’, Ceram. Int., 2009, 35, 1877–1882

[7] M. P. L. N. Rao, G. S. Gupta, P. Manjunath, S. Kumar, A. K. Suri, N. Krishnamurthy and C. Subramanian: ‘Temperature measurements in the boron carbide manufacturing process – a hot model study’, Int. J. Refract. Met. Hard Mater., 2009, 27, (3), 621–628