Synthesis of ultrahard material under no pressure: Mechanical properties

✍ Scribed by Cordelia Sealy

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 79 KB
• Volume: 10
• Category: Article
• ISSN: 1369-7021
• DOI: 10.1016/s1369-7021(07)70113-x

✦ Synopsis

Angeles (UCLA) have found an ultrahard material, rhenium diboride (ReB 2 ), that can be synthesized under ambient pressures [Chung et al., Science (2007) 316, 436]. Many industrial applications require superhard materials as abrasives or for cutting tools and scratchresistant coatings. While diamond is the ultimate superhard material with the highest known hardness, there are applications for which diamond is unsuitable, e.g. the cutting of steel and ferrous metals, because it produces Fe carbide during high-speed machining.

The traditional approaches to synthesizing alternative superhard materials rely on high pressures. Cubic BN, the second hardest material and suitable for use in cutting steel, requires extreme pressures (>5 GPa) and temperatures (>1500ºC) for its synthesis.