Semiconducting Superhard Ruthenium Monocarbide
The ruthenium monocarbide (RuC) structure was investigated through a density functional theory based on the 10 structures of known transition-metal compounds. The calculations indicated that zinc blend structured RuC (ZB-RuC) is the most energetically stable at the ground state, and the calculated lattice parameters are more consistent with the experimental values than those recently reported of rock salt structured RuC (RS-RuC). The structural stability of RuC was studied by calculating total energy, elastic constants, and phonon frequencies. Only ZB-RuC showed dynamical stability. It can be concluded that the most likely structure of the synthesized RuC is ZB-RuC rather than RS-RuC. From the calculated band structure and density of states (DOS), it was found that ZB-RuC is a semiconductor while other RuC structures are metallic. The estimated hardness indicates that ZB-RuC is a new superhard material with a Vickers hardness value of 42.8 GPa, compared with B4C. Even though it is a superhard material, the high B/G value (3.95) indicates that ZB-RuC is still a ductile material.
Zhisheng Zhao Meng Wang Lin Cui Julong He Dongli Yu Yongjun Tian
State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
国际会议
武汉
英文
155-158
2010-09-01（万方平台首次上网日期，不代表论文的发表时间）