CONSPECTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining industries.Because of their high hardness and wear resistance,superhard materials(Vi...CONSPECTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining industries.Because of their high hardness and wear resistance,superhard materials(Vickers hardness,Hv≥40 GPa)are commonly used as cutting tools and abrasives.Although diamond is the hardest known material used for industrial applications,its synthesis requires both high pressure and high temperature.Interest in the field of superhard materials research has led to the search for alternatives with high hardness and thermal stability at low cost.The discovery of novel ultraincompressible,superhard materials has largely developed through trial and error along two paths.In one approach,researchers combine light elements,such as boron,carbon,nitrogen,and oxygen,often at high pressure,to replicate the highly directional,dense,covalent bonds of diamond.In the second approach,these light elements(B,C,N,and O)are combined with highly incompressible,electron-rich transition metals to form dense covalently bonded networks at ambient pressure.展开更多
基金This work was supported financially by the National Science Foundation Division of Materials Research under grant DMR-2004616(R.B.K.and S.H.T.)Additional support was provided by the Dr.Myung Ki Hong Endowed Chair in Materials Innovation(R.B.K.)+5 种基金SuperMetalix,Inc.(R.B.K.),and a UCLA Graduate Division Dissertation Year Fellowship(L.E.P.)Data reproduced in this manuscript made use of beamline 12.2.2 at the Lawrence Berkeley National Laboratory(LBNL)Beamline 12.2.2 at the Advanced Light Source is a DOE Office of Science User Facility supported under contract no.DE-AC02-05CH11231High pressure research on beamline 12.2.2 is also partially supported by COMPRESthe Consortium for Materials Properties Research in Earth Sciences under NSF Cooperative Agreement EAR 1606856.The authors thank Dr.Abby Kavner,Dr.Reza MohammadiSabina C.Cabrera for contributing to this work.
文摘CONSPECTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining industries.Because of their high hardness and wear resistance,superhard materials(Vickers hardness,Hv≥40 GPa)are commonly used as cutting tools and abrasives.Although diamond is the hardest known material used for industrial applications,its synthesis requires both high pressure and high temperature.Interest in the field of superhard materials research has led to the search for alternatives with high hardness and thermal stability at low cost.The discovery of novel ultraincompressible,superhard materials has largely developed through trial and error along two paths.In one approach,researchers combine light elements,such as boron,carbon,nitrogen,and oxygen,often at high pressure,to replicate the highly directional,dense,covalent bonds of diamond.In the second approach,these light elements(B,C,N,and O)are combined with highly incompressible,electron-rich transition metals to form dense covalently bonded networks at ambient pressure.
