Preparation of zirconium boride based composite ceramic powder and ablative resistance of spraying coating 2025-04-12

Ultra-high temperature ZrB2/MoSi2 ceramic coating can effectively improve the high temperature ablation resistance of C/C ceramic matrix composites. The composite powder was prepared by spray drying agglomeration granulation method, and then the composite powder was densified by plasma densification process. The influence of plasma densification process parameters on the properties of the treated powder was studied. After plasma densification, the bulk density and fluidity of the powder were significantly improved. The loose pack density and fluidity of ZrB2/MoSi2 powder were 3.26 g/cm3 and 21.5s /50g, respectively. Compared with agglomerated powder, the loose pack density and fluidity were increased by 108.97 % and 59.01 %, respectively. After densification, the oxygen content of the powder was reduced to 0.05 wt.%. The ZrB2/MoSi2 composite powder was almost not oxidized during the plasma densification process. The ablation test of the plasma spraying coating shows that the coating structure is intact and no spalling occurs after ablation, which indicates that the prepared ZrB2/MoSi2 coating has good high-temperature ablation resistance.

Scientists have developed active metal borides and will begin to develop products such as powders and patches 2025-04-05

Korea Advanced Institute of Science and Technology JMCA: Joule heating helps MXene composites to synthesize efficiently, significantly improving catalytic performance 2025-03-15

Effect of molybdenum disilicide addition on the silicon infiltration of graphite 2025-03-01

The "carrier" of high temperature material: zirconium carbide 2025-02-22

Carbon fiber composite materials: the future star in the military industry, high-performance multifunctional materials 2025-02-08

Study on preparation technology of high purity vanadium ingot for processing 2025-01-11

In view of the characteristics of vanadium metal, such as hydrogen storage, high temperature superconductivity, small fast neutron absorption cross section and corrosion resistance to liquid sodium, the market demand for vanadium metal products is increasing, and these vanadium products must be processed using high purity vanadium ingots to meet the requirements. The preparation technology of high purity vanadium ingot is described in detail from the aspects of raw materials, process principle and flow, production impact factor, etc.

Molybdenum disilicide and its composite materials are summarized 2025-01-04

Synthesis method and application of rare earth hexaboride 2024-12-21

In rare earth borides, boron shows many unique physical and chemical properties because of its lack of electronic properties. There are six kinds of rare earth borides, namely RB2, RB4, R2B5, RB6, RB12 and RB66, among which RB6 cathode material has the characteristics of high melting point, high hardness, low evaporation rate and good chemical stability of non-metallic insoluble compounds, and is a functional material with excellent emission performance. With the continuous development of ion beam and electron beam applications, people have put forward higher requirements on the performance of cathode materials, hoping to further improve the electron emission density, extend the service life and reduce the working temperature. Many researchers have been committed to the preparation process, structure, properties and physical and chemical properties of RB6 research, and achieved phased results. In this paper, the preparation methods of RB6 powder, single crystal and polycrystal are briefly introduced, and the method of preparing PrB6 and (LaxPr1-x) B6 by using SPS (discharge plasma sintering technology) is emphasized. The development of new RB6 cathode materials is explored and its application fields are studied.

Basic research and application prospect of a new superconductor magnesium diboride (MgB2) 2024-12-21

This paper introduces the discovery, research progress and application prospect of a new superconductor magnesium diboride.) Both theory and experiment have proved that the superconductivity of magnesium diboride comes from the coupling of electric phonons, which can be described by the BCS image with S-wave symmetry wave function.) However, in the superconductor of magnesium diboride, it is found that there are two superconducting bandgaps, one at 6meV. The other one is around 2meV, and they both open at the superconducting transition temperature, which brings something new to the study of superconductivity mechanisms.) In mixed state physics, it has been found that there is a large gap between the boundary between superconductivity and normal state (upper critical magnetic field He2) and the flux melting line (irreversible line Hirr), even at absolute zero. The author proposed that this may be due to the result of the double energy gap or the quantum melting of the magnetic flux matter) In terms of application, it is most likely to make it into a superconducting magnet, using a closed cycle refrigerator to refrigerate at about 20K, which is very likely to replace the liquid helium temperature superconducting magnet used in nuclear magnetic resonance imaging in medicine today).

The Past, Present, and Future of Mxenes Materials 2024-09-21

A Review of Vanadium Application Research 2024-07-04