Preparation method of a core-shell structure iron-coated ceramic composite powder

Abstract

The invention discloses a method for preparing a core-shell structure iron-coated ceramic composite powder. The preparation method comprises the following steps: 1) select ceramic particles, place them in a fluidized bed, and fluidize them with a mixture of hydrogen and argon. The gas passes through the fluidized bed to make the ceramic particles in a fluidized state; 2) heating the ceramic particles in a fluidized state; 3) heating the iron precursor, using argon as the carrier gas, entraining the iron precursor vapor into the fluidized bed reaction section 4) The chemical vapor deposition reaction is carried out in the reaction section area of ​​the fluidized bed; 5) After the reaction is completed, it is cooled to room temperature with argon protection to obtain a core-shell structure iron-coated ceramic composite powder. The composite powder of the invention has the advantages of pure product, no impurity pollution, strong binding force between the iron coating layer and the ceramic matrix, uniform distribution of iron on the surface of the powder, controllable content and the like. The method for preparing the composite powder of the present invention has the advantages of simple process, mild reaction conditions, and convenience for large-scale and continuous production.

Description

technical field [0001] The invention belongs to the field of metal-ceramic composite materials, and in particular relates to a method for preparing a core-shell structure iron-coated ceramic composite powder material. Background technique [0002] Due to its excellent strength, thermal hardness, chemical stability, anti-wear and oxidation resistance and many other advantages, ceramic materials have broad application prospects in many aspects such as cutting, forming and anti-wear coating. However, due to the poor toughness of ceramic materials and the difficulty of direct compression molding, etc., the modification of ceramic materials by adding metal elements has become an important means at present. Studies have shown (Alireza Jam, Leila Nikzad, Mansour Razavi, TiC-based cermet prepared by high-energy ball-milling and reactive spark plasma sintering, Ceramics International, 2017, 43:2448-2455), due to the excellent fracture toughness and phase Capacitive, non-toxic, wide ...

AI Technical Summary

Problems solved by technology

At present, the main methods for preparing iron-reinforced metal-ceramic composites include mechanical alloying, casting, and self-propagating high-temperature synthesis, but these methods have the following problems: mechanical alloying is difficult to achieve uniform mixing of iron and ceramics, and due to The ceramic material has high hardness and serious wear, which is easy to cause pollution to the product; the casting method is easy to form pores and inclusions, and the interface is prone to reaction, which requires high wettability between the surface of the iron and the ceramic substrate, and due to the presence of iron and ceramic materials The difference in density may easily cause segregation; the composite powder prepared by the self-propagating high-temperature synthesis method has problems such as uneven distribution of elements, easy agglomeration, and high energy consumption.

The traditional electroless plating and electroplating methods are complicated in process, and the ceramic particles need to undergo complicated pretreatment processes such as roughening, activation, and sensitization, which are expensive; and it is easy to introduce impurity salts; the agitation uniformity changes during the enlarged production process, resulting in coating Uneven or even a large amount of self-nucleating metals; the reaction process produces a large amount of toxic and harmful waste liquid, which is easy to cause environmental pollution

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