7 results about "Boron carbide" patented technology

The invention discloses an additive manufacturing method for in-situ regulation and control of a TiB / TiC titanium-based heterostructure through laser deposition, and belongs to the technical field of composite material preparation. According to the method, laser path planning is carried out based on three-dimensional modeling and layered slicing; the preparation method comprises the following steps: ball-milling and mixing titanium alloy powder, nano boron carbide powder and trace rare earth powder according to a specific proportion, and carrying out vacuum drying; and addition of trace rare earth is beneficial to grain refinement and improvement of reinforcement phase distribution and interface bonding. Under the action of a high-energy laser beam, the mixed powder is fused in an argon protective atmosphere, an in-situ reaction is carried out at the same time, and TiB and TiC reinforced phases are generated; the gradient component design can be implemented in the laser deposition process, specifically, the powder feeding proportion of B4C powder is dynamically controlled through a program, the gradient of the B4C powder is increased from the bottom layer to the surface layer in the direction perpendicular to the substrate, and therefore the gradient heterostructure with the enhanced phase content and performance gradually changed is formed. According to the method, the problems of non-uniform reinforcement phase distribution, obdurability mismatch, plasticity loss and the like in a traditional method are solved, the prepared composite material or gradient component has high strength (the tensile strength reaches 987.66 MPa) and good plasticity and toughness matching, no crack defect exists, and the method is suitable for manufacturing of high-performance parts in the fields of aerospace and high-end machine manufacturing.

This invention discloses a fissure grouting material, its preparation method, and its application, belonging to the technical field of radiation protection engineering materials. By mass, its raw materials include: 45-60 parts barite sand, 25-35 parts sulfoaluminate cement, 8-20 parts borax, 2-5 parts boron carbide powder, 1-5 parts nano-gadolinium oxide, 5-15 parts lithium slag powder, 3-8 parts barium sulfate whiskers, 3-8 parts polymer emulsion, 0.5-1.5 parts water-reducing agent, 0.1-0.5 parts stabilizer, and 18-25 parts water. This invention provides high-density gamma-ray shielding through barite sand, achieves all-round neutron protection through a quaternary composite neutron absorption system, enhances the material's toughness and shielding effect through barium sulfate whiskers, and ensures high fluidity and interfacial bonding strength of the grout through the polymer emulsion. This material is particularly suitable for sealing and shielding fissures in the surrounding rock of radioactive tunnels, possessing advantages such as excellent shielding effectiveness, good construction performance, high volume stability, and long-term durability.

A trimming blade and a hair trimming tool. The trimming blade comprises a blade body (1) and an insert (2); the blade body is suitable for being mounted on a hair trimmer; the insert is connected to the blade body; the insert is suitable for being in frictional contact with a fixed blade or a movable blade; the insert is a ceramic member; one side of the blade body is provided with first blade teeth (11); one side of the insert is provided with second blade teeth (21); the second blade teeth correspond to the first blade teeth; the second blade teeth are suitable for cooperating with the fixed blade or the movable blade to trim hair. The insert is made of a plate-shaped boron carbide ceramic piece or cubic boron nitride piece, and is in direct contact with the fixed blade or the movable blade, thereby achieving lower frictional heating temperature, slow temperature rise, better sharpness and higher wear resistance; the insert performs the functions of contacting with the fixed blade or the movable blade and cutting hair, so that the material selection range for the blade body is wider, that is, a material having lower density can be selected to make the entire blade lighter in weight; the insert is not prone to breaking.

The invention relates to a refractory material technology, in particular to a high-slag-resistance low-emission magnesia carbon brick and a preparation method thereof, and the high-slag-resistance low-emission magnesia carbon brick comprises the following components: magnesia, graphite, aluminum-silicon alloy, magnesium aluminate spinel, calcium zirconate, modified cardanol resin, boron carbide, nano silicon carbide, magnesium carbonate, carbon nanotubes and nano magnesium oxide. And the bio-based modified resin is used for replacing the traditional phenolic resin, so that the high-temperature carbonization residual carbon rate and the breaking strength are improved, and the VOC emission is obviously reduced. In the gradient structure design, the outer layer has the oxidation weight loss rate at 1600 DEG C through a composite anti-oxidation mechanism of a nano silicon carbide coating and boron carbide; a high-melting-point phase (CaZrO with the melting point of 2345 DEG C) generated by the magnesium aluminate spinel and the calcium zirconate in the middle layer constructs a slag-resistant defense line, so that the penetration depth of slag is reduced; and the thermal shock resistance of the inner layer is remarkably improved by virtue of high graphite content and a carbon nanotube network.

A method for preventing the deposition of schillerization on the surface of normal pressure solid phase sintered silicon carbide ceramic; including at least one of the following steps: a step before sintering, a step during sintering or a step after sintering; the step before sintering includes covering the surface of the sintered sample with graphite paper, or spraying a boron carbide ceramic coating or a boron nitride ceramic coating on the surface of the sintered sample; the step during sintering includes reducing the maximum sintering temperature from 2200 DEG C to 2050-2100 DEG C, while extending the holding time by 0.5-1 hour, or increasing the gas flow of the protective gas by 5-15 m 3 / h; the step after sintering includes placing the silicon carbide ceramic product into a container containing molten NaOH for high temperature corrosion, effectively reducing the surface roughness of the sealing material, realizing near net size forming of the silicon carbide ceramic sealing element, and having great practical significance for reducing production cost.

The application provides a carbon-based ceramic side sealing plate for thin strip continuous casting and a preparation method thereof. ® N1055 and T85 are weighed and stirred uniformly to obtain a mixture, deionized water is added and stirred to form a slurry; then the slurry is subjected to spray drying, mixed with liquid phenolic resin, and granulated to obtain a granulation powder; the granulation powder is placed in a mold, and near-net-size forming is performed by using a hydraulic machine to obtain a green body; the green body is solidified; the solidified green body is placed in a sagger, and is fully buried with silicon powder; the sagger is placed in a vacuum electric furnace for staged sintering, and a carbon-based side sealing plate is obtained. The side sealing plate prepared by the method has the characteristics of low preparation cost and long service life, solves the problem of insufficient anti-friction and wear performance of the side sealing plate, and meets the service requirements of the side sealing plate for thin strip continuous casting in terms of resistance to molten steel corrosion, resistance to molten steel thermal shock, and resistance to friction and wear.