Diamond artificial synthesis

Many new phases of carbon have been discovered as an offshoot of attempts of artificial synthesis of diamond. Among these, a class of amorphous carbon and hydrocarbon phases exhibits properties close to those of diamond. These diamond-like phases are therefore considered to be promising technological materials. 

Towards the end of the 18 century a British chemist, Smithson Tennant, showed that diamonds are composed of nothing but carbon a discovery that gave a more scientific direction to synthesis efforts. By the beginning of the 19 century, it was known that carbonaceous materials, heat and pressure are required for diamond formation. Finally, success in artificial synthesis was achieved in the middle of the 20 century by two routes the High Pressure High Temperature (HPHT) route leading to the formation of diamond grit and the Low Pressure... 

The research effort directed towards artificial synthesis of diamond under low pressure low temperature conditions led to the... 

Diamond, the hardest material known, is the most representative inorganic product of natural and artificial high pressure synthesis. As illustrated later, it can be obtained from graphite at 5.4 GPa and 1667 K, typically, while it is not diamond but graphite that is thermodynamically stable at ambient conditions. Though solid hydrogen cannot be quenched to ambient conditions, diamond can be and remains stable, in effect, to about 600 K. From practical viewpoints, high pressme synthesis is of value if the product has a particular... 

Natural deposits were the sole source of diamond until the mid-1950s as there was no synthesis of artificial material available-despite a variety of approaches. 

Following the February 15, 1955, synthesis announcement by the General Electric Co., several claims to prior synthesis were voiced. Only one of these claims has appeared in a technical journal. It appeared as an article entitled Artificial Diamonds by H. Liander in the ASEA Allmanna Svenska Elektriska Aktiebolaget, Vasteras, Sweden) Journal for May-June of 1955. The method of synthesis was not given but the statement was made that ASEA produced its first diamonds on 15th February, 1953. The experimental procedures used were disclosed in 1960 and were similar to those used at General Electric. ... 

The synthesis of artificial diamond from graphite requires elevated pressure (about 54 kbar), high temperature (1500°) and catalysts (transition metals) as reviewed earlier [2,16-20 cf. also item 4.1 below. 

The first artificial diamond synthesis was conducted by the Swedish company ASEA with a six-anvil press in February 1953 (Jackson and Davim 2011). In 1955, General Electric (GE)... 

The invention of cubic boron nitride (CBN) is closely linked to the synthesis of artificial diamond. Cubic boron nitride synthesis was conducted first in 1957. CBN crystals are produced from boron and nitrogen at high pressures of 50-90 kbar, high temperatures between 1,800 °C and 2,700 °C, and in the presence of a catalyst (Klocke 2009). During the first years on the market, CBN was seen as a competitor to diamond. However, CBN proved to be a better material for machining of hard-to-machine ferrous materials than diamond due to the missing chemical affinity and the higher thermal stability. 

In the 1950s to 1980s, two main techniques were developed for the synthesis of artificial diamond (a) high-pressure/high-temperature synthesis that yielded artificial diamond gems [18], and (b) chemical vapor deposition (CVD) [19] that made possible the synthesis of diamond in thin-film form on various substrates. Different CVD techniques have been adopted in the synthesis of diamond thin films. Three main CVD techniques include hot-filament CVD [20], plasma-assisted CVD [21], and combustion CVD [22]. There are many types of plasma-assisted CVD techniques according to the energy sources, such as the microwave plasma-assisted CVD (also... 

Due to its unique physicochemical characteristics, diamond is widely used in industry. Interest in fabrication of artificial diamond crystals, specifically, those obtained by detonation transformation of explosives, was already evinced in the 1940s. Attention was paid to the fact that thermodynamic conditions for the existence of carbon as diamond crystals are realized in the zone of the detonation complex. Nanodiamond powder synthesis and the properties of synthesized materials were studied in numerous works performed at various research centers [1-11]. In subsequent decades, many attempts were undertaken to develop detonation diamond technology. One of these technologies was developed and patented by the Russian Federal Nuclear Center-Zababakhin All-Russian Research Institute of Technical Physics (RFNC-VNIITF). 

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