Abstract: The invention relates to a rock-cutting tool and a method for manufacturing this tool, which comprises knives comprising a layer of polycrystalline synthetic diamond (PSD), a diamond impregnation layer with diamond particles and bonding cobalt, characterized in that the PSD layer is supported directly, along a planar interface, on the diamond impregnation layer whose interface surface is planar by machining and with which the diamond particles are flush.

Abstract: The invention relates to the field of liquid phase synthesis of diamond or any other allotropic forms of carbon and more particularly to a process of liquid phase synthesis of carbonaceous films, according to which a voltage is applied, in a solution containing carbonaceous molecules, to a substrate on which a carbonaceous layer is to be deposited and photons are sent to the surface of the substrate. To this end, the invention also relates to a device for the liquid phase synthesis of carbonaceous films comprising a synthesis vessel inside which are arranged means for applying a voltage in a reaction zone, and photonic means are arranged to send photons to the reaction zone.

Abstract: The invention relates to the improvement of synthesis by chemical vapour deposition, particularly diamond synthesis. It is proposed to reduce the time required for the deposition of diamond layers by compressing the plasma near the deposition substrate in order to increase the chances of collision between active species.

Abstract: The method involves a substrate 21 near which reagents 25 are provided. Pump (26) and Raman (27) photons make it possible to create a stimulated Raman emission during the synthesis (29) of the material. The Raman emission can be Stokes or anti-Stokes. In one embodiment of the invention, the zone where the synthesis (29) occurs is in an optical cavity and Raman photons (27) emitted by the Raman emission are reoriented toward the zone where the synthesis (29) occurs. In another embodiment of the invention, the zone where the synthesis (29) occurs is not in an optical cavity, and a stream of Raman photons (27) is created in an outside optical cavity before being sent toward the zone where the synthesis (29) occurs. The synthesis (29) preferably involves a CVD method or solidification by the Czochralski method.

Abstract: The method involves a substrate 21 near which reagents 25 are provided. Pump (26) and Raman (27) photons make it possible to create a stimulated Raman emission during the synthesis (29) of the material. The Raman emission can be Stokes or anti-Stokes. In one embodiment of the invention, the zone where the synthesis (29) occurs is in an optical cavity and Raman photons (27) emitted by the Raman emission are reoriented toward the zone where the synthesis (29) occurs. In another embodiment of the invention, the zone where the synthesis (29) occurs is not in an optical cavity, and a stream of Raman photons (27) is created in an outside optical cavity before being sent toward the zone where the synthesis (29) occurs. The synthesis (29) preferably involves a CVD method or solidification by the Czochralski method.

Abstract: Stabilizer-reamer for drilling string characterized in that it comprises a mixture of diamond impregnated inserts, the mixture comprising cutting diamond impregnated inserts and wear resistant diamond impregnated inserts, said wear resistant diamond impregnated inserts having smaller diamond grain size and higher diamond concentration than said cutting diamond impregnated inserts.

Abstract: Method for synthesizing a material by chemical vapor deposition (CVD), according to which a plasma is created in a vacuum chamber in the vicinity of a substrate, and according to which a carbon-carrying substance and H2 are introduced into the chamber in order to produce in the chamber a gas comprising substances carrying reactive-carbon atoms in the form of unsaturated molecules or radicals from which the synthesis of said material will be performed, and in that the electromagnetic absorption and inelastic diffusion spectra of the solid material to be synthesized are used to take from these spectra the absorption frequencies that contribute to the reactions that lead to the formation of the solid material to be synthesized, and in that energetic rays are produced in the form of a photon beam carrying quantities of energy determined by each of the frequencies corresponding to said absorption and inelastic diffusion frequencies, said photon beam being injected into the plasma where, for energy states of the so