7 results about "Diboride" patented technology

The application provides a preparation method of high-purity superfine diboride powder and relates to the field of metal borides. The preparation method comprises the following steps: introducing BCl3 and H2 into a vacuum environment to obtain a mixed gas; mixing the mixed gas and metal wires and performing electric explosion treatment to obtain a reaction powder; and performing passivation ball milling treatment on the reaction powder in a mixed atmosphere of argon and oxygen to obtain the high-purity superfine diboride powder; and the metal wires comprise at least one of titanium wires, magnesium wires and aluminum wires. The method does not introduce by-products and impurities in the whole process, the obtained diboride powder is small in particle size, uniform in distribution and free of agglomeration, the preparation method is short in process and high in efficiency, and the method has a good industrialization prospect.

The application provides a high-pressure corrosion-resistant hard alloy material and a preparation method and application thereof, and belongs to the technical field of alloy materials. The application improves the strength, toughness and corrosion resistance of the material by constructing titanium boride, silicon carbide and chromium diboride hard phases, introduces a multiphase composite binder composed of aluminum-iron alloy, high-entropy alloy and cerium hexaboride to realize high-temperature dense coating, and adopts asymmetric gradient paving and sintering process to construct a gradient structure with high surface hardness, high toughness in the core and stress concentration reduction in the transition layer. Meanwhile, the surface hardness and sealing property are strengthened by powder embedding and calcination, and the wear resistance, corrosion resistance and impact resistance of the material are comprehensively improved.

The invention discloses a wide-temperature-range anti-attrition wear-resistant tungsten diboride-based composite film as well as a preparation method and application thereof. The wide-temperature-range anti-attrition and wear-resistant tungsten diboride-based composite film comprises a chromium transition layer, a chromium / tungsten diboride layer and a tungsten diboride / carbon / nitrogen doped layer which are sequentially stacked on the surface of a base body in the thickness direction of the wide-temperature-range anti-attrition and wear-resistant tungsten diboride-based composite film, the chromium transition layer is adjacent to the surface of the base body, and the tungsten diboride / carbon / nitrogen doped layer is arranged at the top end of the tungsten diboride-based composite film. The preparation method comprises the following steps: sequentially depositing the chromium transition layer, the chromium / tungsten diboride layer and the tungsten diboride / carbon / nitrogen doped layer on the surface of the substrate by adopting a magnetron sputtering technology to prepare the wide-temperature-range anti-attrition wear-resistant tungsten diboride-based composite film. The tungsten diboride-based composite film still keeps a low friction coefficient and a low wear rate under a high-temperature condition, and synchronous improvement of structural toughness and high-temperature lubricating performance is realized.

Disclosed is a ceramic sintered body which can give consideration to both toughness and wear resistance. This ceramic sintered body contains a first compound and a second compound. The first compound is silicon carbide, and the second compound is a diboride of a Group 4 element. The proportion of the second compound in the ceramic sintered body is 50% by mass to 70% by mass. When a 300 [mu] m * 300 [mu] m region of the polished surface of the ceramic sintered body is divided into 400 sections of 15 [mu] m * 15 [mu] m, and the area ratio of the first compound is determined for each of the sections, the coefficient of variation CV of the area ratio of the first compound is greater than 0.14 and less than 0.23.

The invention belongs to the field of ultrahigh-temperature ceramic materials, and particularly relates to high-temperature-resistant antioxidant multi-component diboride ceramic powder as well as a preparation method and application thereof. The chemical formula of the high-temperature-resistant antioxidant multi-component diboride ceramic powder is (Ti < 0.2 > Zr < 0.2 > Hf < 0.2 > Nb < 0.2 > Sc < 0.2 >) B2 or (Zr < 0.2 > Hf < 0.2 > Nb < 0.2 > Sc < 0.2 > Lu < 0.2 >) B2 or (Zr < 0.2 > Hf < 0.2 > Nb < 0.2 > Sc < 0.2 > Yb < 0.2 >) B2. The prepared high-temperature-resistant antioxidant multi-component diboride powder is of a single-phase hexagonal structure, and the initial oxidation temperature is effectively increased through the synergistic effect of multiple elements. Experimental results show that the initial oxidation temperature of the high-temperature-resistant antioxidant multi-component diboride ceramic powder disclosed by the invention is 687.1-788.0 DEG C, which is higher than the initial oxidation temperature of typical single-component diboride powder. Therefore, the multi-component diboride ceramic powder prepared by the preparation method disclosed by the invention has excellent oxidation resistance.

This invention belongs to the field of ceramic preparation technology and provides a hot-pressed sintered multiphase boron carbide ceramic and its preparation method. The ceramic is based on boron carbide, with the addition of high-entropy diboride phases containing titanium, zirconium, hafnium, niobium, tungsten, and molybdenum, as well as a carbon phase. The ceramic may further contain corresponding high-entropy carbides. In the preparation process, multi-metal powder, amorphous boron powder, cobalt powder, and a process control agent are first subjected to high-energy ball milling and heat treatment under an inert atmosphere to obtain high-entropy diborides. Then, nanodiamond and cobalt powder are dispersed in ethanol, followed by ultrasonication, drying, and heat treatment to obtain the carbon phase. Subsequently, this carbon phase is mixed with boron carbide and granulated to obtain composite particle powder. Finally, it is hot-pressed and sintered in segments under vacuum conditions, with pressure pulses and pressure relief cycles applied during the high-temperature stage to obtain a dense multiphase ceramic, which can be applied to ceramic valves and ceramic cylinder valve plates.

This invention discloses a boron-doped vanadium diboride-based multiphase ceramic and its high-pressure, high-temperature preparation method. The ceramic consists of vanadium diboride and a boron-doped phase, with a boron doping amount of 15–50 vol%, preferably 50 vol%. The preparation method involves weighing VB2 powder and boron powder according to a specified ratio, ball-milling them together, pressing them into a blank, and then sintering under high pressure and high temperature (1000–2000℃) for 60–180 minutes. This invention, through the synergistic effect of controllable excess boron doping and high-pressure, high-temperature sintering, allows excess boron to form a nanoscale second phase in situ at the VB2 grain boundaries, inducing high-angle, multi-level crack deflection and promoting grain pull-out, thus significantly improving fracture toughness while maintaining high hardness. The obtained 50 vol% boron-doped multiphase ceramic exhibits a Vickers hardness of 21.27 ± 1.11 GPa and a fracture toughness of 9.41 ± 0.58 MPa·m. 1 / 2 This method achieves approximately 135% improvement in hardness and toughness compared to pure VB2 ceramics, realizing a synergistic enhancement of both. The process is simple, requires no additional sintering aids, and is suitable for preparing high-strength, high-toughness ultra-high temperature ceramic components.