Method for preparing high thermal conductivity aluminum nitride powder based on graphene

Abstract

The invention discloses a method for preparing high thermal conductivity aluminum nitride powder based on graphene. The method comprises the following steps of enabling aluminum oxide and the grapheneto be prepared into mixed powder in a mole ratio of (1 to 5)-(5 to 1); enabling the mixed powder to be subjected to nitridation reaction in the atmosphere of nitrogen gas or ammonia gas at the high temperature of 1,200-2,000 DEG C, and maintaining the nitridation reaction for 1-8 hours; introducing reducing gas in the process of nitridation reaction cooling so as to carry out deoxygenization, andcooling to obtain the high thermal conductivity aluminum nitride powder; enabling the powder, which is obtained after the nitridation reaction, to be subjected to low-temperature calcination decarbonization at 500-800 DEG C in the atmosphere of air, maintaining decarbonization time for 0.5-4 hours, and cooling to obtain the high thermal conductivity aluminum nitride powder. The graphene is adopted as a carbon source and has extremely high reactivity and reaction uniformity. In the process of nitridation reaction cooling, the reducing gas is introduced to perform deoxygenization operation, andthe material heat-conducting property is further improved. The method disclosed in the invention has the advantages of low reaction temperature, simple process, low energy consumption, high product performance and the like.

Description

technical field [0001] The invention relates to the technical field of material preparation, in particular to a method for preparing aluminum nitride powder with high thermal conductivity. Background technique [0002] As a new type of ceramic material with excellent comprehensive performance, aluminum nitride has excellent thermal conductivity (theoretical thermal conductivity reaches 320Wm -1 K -1 ), low dielectric constant and dielectric loss, non-toxic, and a series of excellent properties such as thermal expansion coefficient matching silicon, have become the key materials of current research. [0003] At present, there are three main methods for the synthesis of aluminum nitride powder: (1) direct nitriding of aluminum powder. This method has the advantages of rich raw materials, simple process, and suitable for large-scale production, but it is a strong exothermic reaction, the process is difficult to control, and it is difficult to synthesize high-purity, fine-grai...

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Problems solved by technology

The document "Mechanism and kinetics of combustion-carbothermal synthesis of AlNnanopowders" (publishing source: "Ceramics International", author: Qing He; Mingli Qin; MinHuang et al., publication time: April 2017) proposed a method using soluble aluminum sources, A method for preparing aluminum nitride powder from materials such as urea and glucose under a nitrogen atmosphere. Although the reaction temperature of this method is low and the product particles are uniform, the process involves the preparation of a precursor, and the volume expansion of the precursor is too large. During the nitriding process, Compared with other processes, the production capacity of the calciner is greatly reduced

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