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CN-122010573-A - Silicon-containing high-entropy MAB phase ceramic powder and preparation method thereof

CN122010573ACN 122010573 ACN122010573 ACN 122010573ACN-122010573-A

Abstract

The invention relates to the technical field of ceramic materials, in particular to a silicon-containing high-entropy MAB phase ceramic powder and a preparation method thereof. The chemical formula of the silicon-containing high-entropy MAB phase ceramic powder is M 4 CrSiB 2 , wherein M is transition metal, and the stoichiometric ratio of each transition metal is equal to or close to the stoichiometric ratio. The invention takes the simple substance powder as the raw material, and carries out sintering in a way of rapid temperature rise and drop and short-time heat preservation in the Joule heating equipment, thereby effectively avoiding the generation of complex intermediate phases and the loss of volatile raw materials in the sintering process and realizing the precise and rapid preparation of the single-phase silicon-containing high-entropy MAB phase ceramic powder. The preparation method provided by the invention has the advantages of low cost, simple process, high synthesis efficiency, low energy consumption and the like, and is suitable for mass production.

Inventors

  • SUN GUOXUN
  • SUN XIAONING
  • BAO YICHEN

Assignees

  • 山东大学深圳研究院

Dates

Publication Date
20260512
Application Date
20260204

Claims (10)

  1. 1. The silicon-containing high-entropy MAB phase ceramic powder is characterized by having a chemical formula of M 4 CrSiB 2 , wherein M is transition metal, and is selected from at least three of titanium, molybdenum, tungsten, niobium and tantalum, and the stoichiometric ratio of each transition metal is equal or nearly equal.
  2. 2. The method for preparing the silicon-containing high-entropy MAB phase ceramic powder as claimed in claim 1, which is characterized by comprising the following steps: (1) Weighing transition metal powder, chromium powder, silicon powder and boron powder according to a chemical formula M 4 CrSiB 2 ; (2) Carrying out wet mechanical ball milling and vacuum drying on various powder to obtain mixed powder; (3) Compacting the mixed powder liquid in a hydraulic manner to obtain a compact blank; (4) Embedding the blank into a graphite carrier for Joule thermal sintering, and cooling to obtain a block sample; (5) Crushing and grinding the block sample to obtain the silicon-containing high-entropy MAB phase ceramic powder.
  3. 3. The method according to claim 2, wherein in the step (2), the ball milling medium is absolute ethanol or methanol.
  4. 4. The method according to claim 2, wherein in the step (2), the ball milling speed is 200 to 400 rpm, and the ball milling time is 12 to 24 hours.
  5. 5. The method according to claim 2, wherein in the step (2), the drying temperature is 60 to 150 ℃ and the drying time is 8 to 24 hours.
  6. 6. The method according to claim 2, wherein in the step (3), the hydraulic pressure is 150 to 300 MPa and the holding time is 5 to 15 minutes.
  7. 7. The method of claim 2, wherein in step (4), the graphite carrier is selected from the group consisting of graphite paper, graphite felt and graphite plate.
  8. 8. The method of claim 2, wherein in step (4), the reaction is performed under a shielding gas, which is argon or helium.
  9. 9. The method according to claim 2, wherein in the step (4), the temperature rising rate is 10 3 ~10 5 ℃ per minute, the sintering temperature is 1700-1900 ℃ and the heat preservation time is 20-60 s.
  10. 10. The method of claim 2, wherein in step (4), the rate of cooling is 10 3 ~10 5 ℃ per minute.

Description

Silicon-containing high-entropy MAB phase ceramic powder and preparation method thereof Technical Field The invention relates to the technical field of ceramic materials, in particular to a silicon-containing high-entropy MAB phase ceramic powder and a preparation method thereof. Background The disclosure of this background section is only intended to increase the understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art already known to those of ordinary skill in the art. The MAB phase ceramic is a ternary layered ceramic, wherein M is a transition metal element, A is an aluminum or silicon element, and B is a boron element. The material has the properties of metal and ceramic, has the characteristics of good mechanical property, high damage tolerance, oxidation resistance, mechanical processing and the like, and has very wide application prospect in a high-temperature oxidation environment. At present, the related research on MAB phase ceramics mainly focuses on aluminum-containing MAB phase ceramics such as MoAlB and Fe 2AlB2, and reports on silicon-containing MAB phase ceramics are relatively limited. The high-entropy ceramic is a near equimolar multi-component single-phase solid solution ceramic material, and the unique high-entropy effect can lead the high-entropy ceramic to show special advantages in the aspects of mechanical, thermal, antioxidation and the like, however, no report of the silicon-containing high-entropy MAB phase ceramic is yet seen at present, and the variety of the MAB phase ceramic is not beneficial to further expanding. The solid solution atoms are introduced into the M or A position of the MAB phase ceramic to effectively influence the performance of the MAB phase ceramic, so that the M position is simultaneously introduced with a plurality of solid solution atoms to form the silicon-containing high-entropy MAB phase ceramic, and a wider space is hopeful to be provided for the component and performance regulation of the ceramic. However, the preparation of the silicon-containing high-entropy MAB phase ceramic still faces the following bottlenecks: (1) The crystal form and purity of the silicon-containing MAB phase ceramic are closely related to the type and proportion of M-bit transition metal elements. Depending on the components selected, some of the silicon-containing MAB phase ceramics fail to yield high purity target products, e.g., the Ta 4VSiB2 ceramic has a purity of 81wt% and the Ta 4MoSiB2 ceramic has a purity of only 46 wt%. For the silicon-containing high-entropy MAB phase ceramic, the increase of the number of element components improves the difficulty of selecting the types and the proportions of transition metal elements, and a high-purity target product can be prepared only by reasonably selecting the components. (2) The preparation of MAB phase ceramic powder is mainly realized by high-temperature solid phase reaction, which generally comprises a slow temperature rise and fall and long-time heat preservation process. And the preparation of high entropy ceramics often requires longer holding times at higher temperatures to ensure adequate solid solution of the various elements. Raw materials for synthesizing the MAB phase undergo complex intermediate states during slow temperature rise, resulting in products containing various boride or alloy byproducts. For the preparation of the silicon-containing high-entropy MAB phase ceramic, the variety of raw material types leads to more complex intermediate reaction, and the high-purity target product is more difficult to obtain. Moreover, the loss of volatile raw materials can be caused by long-time high-temperature reaction, so that the stoichiometry of each element in the silicon-containing high-entropy MAB phase ceramic powder is difficult to accurately regulate and control. In addition, the conventional high-temperature solid-phase reaction has the problems of lower preparation efficiency, higher energy consumption and the like, and is difficult to realize the efficient synthesis of the silicon-containing high-entropy MAB phase ceramic powder with huge component regulation and control range, thereby being not beneficial to the formation of industrialization and limiting the practical application of the material. Disclosure of Invention In order to overcome the problems, the invention provides a silicon-containing high-entropy MAB phase ceramic powder and a preparation method thereof. In order to achieve the technical purpose, the invention adopts the following technical scheme: In a first aspect of the present invention, there is provided a silicon-containing high entropy MAB phase ceramic powder having a chemical formula of M 4CrSiB2, wherein M is a transition metal selected from at least three of titanium, molybdenum, tungsten, niobium and tantalum, each transition metal being present in a stoic