摘要:
One aspect of the present disclosure provides a composite sheet including a porous sintered ceramic component having a thickness of less than 2 mm and a resin filled into pores of the sintered ceramic component, wherein the curing rate of the resin is 10 to 70%.
摘要:
A method for treating a super-hard structure, the method including heating the super-hard structure to a treatment temperature of at least 500 degrees centigrade and cooling the super-hard structure from the treatment temperature to a temperature of less than 200 degrees centigrade at a mean cooling rate of at least 1 degree centigrade per second and at most 100 degrees centigrade per second to provide a treated super-hard structure. A PCBN structure produced by the method may have flexural strength of at least 650 MPa.
摘要:
A composition having nanoparticles of a boron carbide and a carbonaceous matrix. The composition is not in the form of a powder. A composition comprising boron and an organic component. The organic component is an organic compound having a char yield of at least 60% by weight or a thermoset made from the organic compound. A method of combining boron and an organic compound having a char yield of at least 60% by weight, and heating to form boron carbide or boron nitride nanoparticles.
摘要:
Polycrystalline compacts include non-catalytic nanoparticles in interstitial spaces between interbonded grains of hard material in a polycrystalline hard material. Cutting elements and earth-boring tools include such polycrystalline compacts. Methods of forming polycrystalline compacts include sintering hard particles and non-catalytic nanoparticles to form a polycrystalline material. Methods of forming cutting elements include infiltrating interstitial spaces between interbonded grains of hard material in a polycrystalline material with a plurality of non-catalytic nanoparticles.
摘要:
Disclosed is a method of fabricating a preceramic polymer for making a ceramic material including a metal boride. The method includes providing a starting preceramic polymer that includes a silicon-containing backbone chain and first and second reactive side groups extending off of the silicon-containing backbone chain, reacting a boron-containing material with the first reactive side group to bond a boron moiety to the silicon-containing backbone chain, and reacting a metal-containing material with the second reactive side group to bond a metal moiety to the silicon-containing backbone chain such that the preceramic polymer includes the boron moiety and the metal moiety extending as side groups off of the silicon-containing backbone chain. Also disclosed is a preceramic polymer composition and a metal-boride-containing ceramic article fabricated from the preceramic polymer.
摘要:
A cubic boron nitride sintered body with excellent wear resistance and fracture resistance. The cubic boron nitride sintered body includes 85 to 95% by volume of cubic boron nitride, and 5 to 15% by volume of a binder phase and inevitable impurities. The binder phase has at least three compounds selected from carbides, nitrides, carbonitrides, oxides and mutual solid solutions thereof of Al, V, Cr, Mn, Co, Ni, Nb and Mo. An amount of an aluminum element contained in the cubic boron nitride sintered body is 0.5 to 5% by mass based on a total mass of the cubic boron nitride sintered body. The binder phase is essentially free of both pure metals and alloys consisting of pure metals.
摘要:
A cutting tool includes a base material and a coating formed on the base material. The base material is a sintered body containing 30 to 80% by volume of cubic boron nitride, and a binder. The surface in contact with the coating, of the base material, has a plurality of convex portions made of the cubic boron nitride and a plurality of concave portions made of the binder. A surface roughness Rsub of the surface in contact with the base material, is 0.1 to 0.4 μm. A surface roughness Rsurf of an outermost surface of the coating is 0 to 0.15 μm. A surface roughness Rasurf of the outermost surface of the coating is 0 to 0.1 μm. The surface roughness Rsub of the surface in contact with the coating, of the base material, is greater than the surface roughness Rsurf of the outermost surface of the coating.
摘要:
A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust.
摘要:
A method to fabricate boron nitride nanotubes incorporating magnesium diboride in their structure. In a first embodiment, magnesium wire is introduced into a reaction feed bundle during a BNNT fabrication process. In a second embodiment, magnesium in powder form is mixed into a nitrogen gas flow during the BNNT fabrication process. MgB2 yarn may be used for superconducting applications and, in that capacity, has considerably less susceptibility to stress and has considerably better thermal conductivity than these conventional materials when compared to both conventional low and high temperature superconducting materials.