Ceramic diamond-like carbon

K. H. Er, S. G. So, The mechanical and structural properties of Si doped diamond-like carbon prepared by reactive sputtering., Journal of Ceramic Processing Research, vol. 12, pp. 187-190, 2011. 

Ceramics Carbon (diamond-like carbon, diamond) Anti-wear coatings, bioMEMS Bioinert Lappalainen et al. (2003) and Alakoski etal (2008)... 

As an alternative to the above solutions, oxide glass overcladding with a phosphate jacket has been proposed for the so-called FLOX fibers (Vacha et al. 1987). Although diamond-like carbon (Stein et al. 1983, Tran et al. 1984) and other types of ceramic or metallic hermetic coatings have also been investigated, UV-curable acrylate coatings appear to be currently preferred for HMFG fibers such as those produced by Infrared Fiber Systems Inc., U.S.A. (IFS). 

Volume 1 starts with an introduction into novel ultra hard ceramics including diamond and diamond-like carbon, carbon nitrides and silicon nitrides as well as boron containing carbides, nitrides and carbonitrides. Here we wish to recognize the great fundamental and technological challenge of developing new superhard... 

In Volume 2 ceramic hard materials are highlighted in the light of their applications. Chapter 1 of Part III concisely reviews the history of diamond and diamondlike super abrasive tools while Chapter 2 and 3 are concerned with the application of chemical vapor deposited diamond and diamond-like carbon films. These sections... 

Satisfactory clinical performance of In-Ceram dental restorations has been reported [23], and further improvement of the chemical durability and wear behaviour of these glass/alumina composites has been achieved by using diamond-like carbon coatings [17]. 

Particulates, flakes (e.g., ceramics, hardmetal, diamond-like carbon) Fibers (e.g., SiC or B C monofilaments, whiskers)... 

The carbon clusters afford some interesting optical properties to the SiOC and Sic films [79], but are also responsible for the high hardness measured on irradiated films (see Table 4), This is at least two times larger than that of eonventionally annealed specimens, mainly because of the previously mentioned diamond-like nature of the C precipitates in the amorphous SiOC or SiC ceramic matrix of irradiated specimens. The effect depends on the type of irradiating ion, but also on the nature of the side groups of the polymeric chain (CH3 vs. C6H5) [59,60]. The annealing of irradiated films does not seem to affect much their hardness. 

Ceramics are usually associated with mixed bonding—a combination of covalent, ionic, and sometimes metallic. They consist of arrays of interconnected atoms there are no discrete molecules. This characteristic distinguishes ceramics from molecular solids such as iodine crystals (composed of discrete h molecules) and paraffin wax (composed of long-chain alkane molecules). It also excludes ice, which is composed of discrete H2O molecules and often behaves just like many ceramics. The majority of ceramics are compounds of metals or metalloids and nonmetals. Most frequently they are oxides, nitrides, and carbides. However, we also classify diamond and graphite as ceramics. These forms of carbon are inorganic in the most basic meaning of the term they were... 

There is presently much effort in basic science and applied research to work on novel ceramic hard materials denoted as super- or ultra-hard materials that can compete with the hardness of conventional diamond. Aim and scope of the research in this field is to develop hard materials with superior mechanical and chemical properties and with similar hardness. Moreover, calculations of properties of hypothetical carbon nitrides like C3N4 indicated that there might be compounds exhibiting even higher hardness values than that of diamond. The low-temperature synthesis of diamond and cubic boron nitride on the one hand as well as the successful research on new carbon nitrides on the other hand have caused an enormous impact around the world on both the basic science and the technological development of these novel ultra-hard materials. 

Ceramics can be elementary i.e., they may consist of only one element (carbon, for example, can exist in two different ceramic forms, as diamond or graphite), or they can be compounds of different elements. Of technical importance are silicate ceramics, containing silicon oxide (for example, porcelain or mullite), oxide ceramics i.e., compounds of metallic elements with oxygen (for example, aluminium oxide AI2O3, zirconium oxide Zr02, or magnesium oxide MgO), and non-oxide ceramics i. e., oxygen-free compounds like silicon carbide and silicon nitride. 

Frequently, the crystal structure of ceramics is more complex than that of metals. Even an elementary ceramic, like diamond, does not crystallise in the cubic or hexagonal structure typical of metals. Because carbon in diamond is covalently bound with a valency of 4, each carbon atom has four nearest neighbours. A unit cell of the forming three-dimensional network is shown in figure 1.13. As can be seen, the structure of the diamond lattice is cubical, but it is not a Bravais lattice because it does not look the same from each atomic site. 

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