Argonne has an invented an innovative method for synthesizing compositionally pure calcium boride at the nanoscale using two different precursors.
Calcium hexaboride, also known as calcium boride (CaB6), is a chemically inert powder known for its stability, exquisite hardness, high melting point and high electrical conductivity. Interestingly, although neither of the two elements that comprise calcium boride is magnetic, as a compound, calcium boride is highly magnetic. All of these properties make calcium boride a highly attractive candidate for use in numerous industries, including electronics, aerospace and energy.
Currently, no other commercial attempts to synthesize calcium boride have been successful, owing to high cost, low purity of outcomes or particles that ranged widely in size. In one of Argonne’s new processes, calcium carbonate powder was coated with carbon by cracking propylene (C3H6) at 550° C. Carbon deficiency was compensated for by adding additional carbon black powder. This was then mechanically mixed with B4C. In a second new process, the precursor was prepared by mechanically mixing boric acid, calcium carbonate and carbon black. In both cases, the precursor material was treated at 1600° C for four hours under flowing argon.
- Stability, hardness, high melting point and conductivity of calcium boride
- Makes calcium boride readily available for manufacturing processes in many industries
Applications and Industries
- Manufacture of boron-alloyed steel
- Deoxidation agent in the production of oxygen-free copper
- Surface protection, abrasives, tools and wear-resistant materials
- Battery cathodes
- N-type thermoelectric materials
Reduced to practice. The next step is scale-up to commercial production.