Introduction of Calcium hexaboride

Calcium hexaboride (CaB6) is a divalent alkaline-earth cubic hexaboride characterized by low density (2.45 g/cm3 ), high melting point (2235°C), high hardness/Young’s modulus [27 GPa (Hv)/379 GPa], high electrical conductivity, as well as good chemical stability. In addition, it has several other unique properties, including low work function, stable specific resistance, low thermal expansion coefficient (within certain temperature ranges), high-temperature weak ferromagnetism, and high neutron absorbability. These excellent properties make CaB6 a highly attractive candidate material for many important applications, e.g., as a boron source in manufacturing boron-alloyed steel, a deoxidizing agent for the production of oxygen-free copper, an antioxidant for carbon-containing refractories, an abrasive or wear-resistant material, a neutron absorbent, and a ferromagnetism material. The techniques/methodologies used for the CaB6 powder synthesis include direct elemental reaction, borothermal or borocarbide reduction, mechanochemical treatment or combustion-assisted metallothermic reduction, solution-based processing, molten salt electrolysis, floating zone method, and aluminum flux method. Unfortunately, these techniques suffer from at least one of the following drawbacks: the use of expensive and hazardous raw materials/ precursors (e.g., elemental boron, calcium, and NaBH4), the requirement of specialty equipment/reaction vessels and high processing temperature/pressure, or long processing time, heavy agglomeration and poor purity of final products, and high overall production cost. The authors have recently successfully synthesized ZrB2, LaB6, and TiB2 ultrafine powders via magnesiothermic reduction of oxide-based raw materials in molten chloride salts. In this work, such a molten salt synthesis (MSS) technique was further extended and modified to provide an alternative approach to the low-temperature synthesis of high-quality CaB6 nanoparticles from cost-effective oxide-based precursors. The effects of salt type, Mg amount, and firing temperature and time on the CaB6 formation were investigated, based on which the synthesis conditions optimized and the responsible mechanisms underpinning proposed. If you are looking for high quality, high purity, and cost-effective Calcium hexaboride, or if you require the latest price of Calcium hexaboride, please feel free to email contact mis-asia.