Mechanical properties of diamond

Table 1. Mechanical Properties of Diamond and Other Hard Materials, GPa ...

Mechanical properties of diamond-like carbon (DLC)thin films... 

Mechanical Properties. Measurement of the mechanical properties of diamond is complicated, and references should be consulted for the various qualifications (7,34). Table 1 compares the theoretical and experimental bulk modulus of diamond to that for cubic BN and for SiC (29) and compares the compressive strength of diamond to that for cemented WC, and the values for the modulus of elasticity E to those for cemented WC and cubic BN. 

Catledge, S., and Vohra, Y., Effect of nitrogen addition on the microstructure and mechanical properties of diamond films grown using high-methane concentrations. /. App. Phys. 86 (1), 698-700 (1999). 

Gielisse, P.J. (1998). Mechanical properties of diamond, diamond films, diamondlike carbon and like-diamond materials. In Handbook of Industrial Diamonds and Diamond Films (M.A. Prelas, G. Popovici, and L.K. Bigelow, eds). Marcel Dekker, Chapter 3, pp. 49—88. 

Table 1 physical and mechanical properties of Diamond, TiB2 and Si... 

Like in any material, the mechanical properties of diamond films have chemical reasons. The basic effect underlying friction is the making and breaking of... 

These defects are generally detrimental to electronic, thermal and mechanical properties of diamond films, although in some cases they may be neutral or beneficial. The frequently occurring defects appear to be stacking faults (twinned clusters with many re-entrant surfaces/comers), which are deemed to play a major role in enhancing diamond growth rates.t ... 

K. Baba, and Y. Aikawa, Mechanical properties of diamond films by a filament assisted chemical vapor deposition, NEC Research and Development, 34 (2) 176-182 (1993)... 

C.J. McHargue. Mechanical Properties of Diamond and Diamond-Like Films. In Y. Tzeng, M. Yoshikawa, M. Murakawa, and A. Feldman, editors, Applications of Diamond Films and Related Materials. Materials Science Monographs, Volume 73. Elsevier, New York, 1991, p. 113. 

The mechanical properties of diamond are summarized in Tabie 11 The properties were measured on single-crystal diamond either naturai or produced by high pressure. For comparison purposes, the table includes the properties of a high-strength ceramic, namely alumina. 

Cubic BC2N. Hetero-diamond B C—N compounds have recently received a great interest because of their possible applications as mechanical and optical devices. The similar properties and structures of carbon and boron nitrides (graphite and hexagonal BN, diamond, and cubic BN) suggested the possible synthesis of dense compounds with all the three elements. Such new materials are expected to combine the best properties of diamond (hardness) and of c-BN (thermal stability and chemical inertness). Several low-density hexagonal phases of B,C, and N have been synthesized [534] while with respect to the high-density phases, different authors report contradictory data [535-538], but the final products are probably solid mixtures of c-BN and dispersed diamonds [539]. 

Included in the most popular test methods in this group is hardness determination with the Shore sclerometer. Dynamic hardness (HSb) is taken as the criterion in estimating the comminution resistance of brittle bodies, and it has found wide use in the study of the mechanical properties of rocks. The method consists of lowering a beater terminating in a diamond ball onto the surface under test (Fig. 4.4.20) and measuring the... 

Tabor D., 1965, The influence of temperature on the mechanical properties of hard crystals, Diamond Research, Inf. Diam. Review. Supplement, 2-5. 

The carbides and nitrides are well known for their hardness and strength, and this section will briefly compare a number of these properties with those of the pure metals. Concentration will be placed here on the first row compounds, since these constitute a complete series, and Mo and W, since these are the most commonly studied metals. As will be shown, the physical and mechanical properties of carbides and nitrides resemble those of ceramics not those of metals. Comparisons will be made with boron carbide (B4C), silicon carbide (SiC), aluminium nitride (AIN), silicon nitride (Si3N4), aluminium oxide (A1203), and diamond, as representative ceramic materials. 

Summary. The interplay between electrical and mechanical properties of suspended, doubly clamped carbon nanotubes in the Coulomb blockade regime is studied theoretically. In this geometry, the capacitance between the nanotube and the gate depends on the distance between them. We find that the tube position changes in discrete steps every time an electron tunnels onto it. Edges of Coulomb diamonds acquire a (small) curvature. Eigenffequencies are modified by Coulomb blockade in a discrete fashion. 

In this Datareview, we have reviewed the mechanical properties of the group III nitrides. From this point of view, they form a very homogeneous family of compounds, with large elastic moduli, both compressional and shear, and bulk moduli of the same order of magnitude as that of diamond. 

The excellent properties of the diamond like materials combined with the low deposition temperature and high deposition rate, make these coatings very promising materials for the future. They have many potential applications as protective coatings for industrial products. Of course the properties of diamond like films never match those of diamond. The films are intrinsically smooth and amorphous, and can be used in coating applications where a plane, mechanically hard and wear/corrosion resistant surface is desirable. 

To investigate the influence of self-organization on the mechanical properties of the composites, the compacts were cut into test pieces 5 x 3 x 20 nun in size with a diamond saw for a three-point bending test. The three-point bending tests were performed at a crosshead speed of 500 pm/min and a span of 15 nun with... 

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