Self-spreading metallurgical process of preparing LaB6 powder

Abstract

The self-spreading metallurgical process of preparing LaB6 powder adopts La2O3, B2O3 and Mg in the mass ratio of 100 to 115-140 to 160-170 as material, and includes the steps of: mixing material and pressing into block; setting inside self-spreading reaction furnace and detonating directly or in constant temperature mode to initiate self-spreading reaction; cooling naturally after reaction to obtain primary product; lixiviating with dilute as lixiviating agent at room temperature, reinforced lixiviating of the filtered extract of the foregoing step with hydrochloric acid as lixiviating agent, filtering, washing and stoving to obtain LaB6 powder. The present invention has low material cost, low power consumption, simple operation and relaxed technological conditions. The product obtained through self-spreading produce producing process has high purity, small granularity, high activity and other advantages.

Description

technical field [0001] The invention belongs to the technical field of boride powder material preparation methods, in particular to the preparation of LaB by a self-propagating metallurgical method 6 powder method. Background technique [0002] LaB 6 It has the characteristics of high melting point, high strength and high chemical stability, and it also has many special functions, such as: low electronic work function, constant specific resistance, zero thermal expansion value in a certain temperature range, low volatility, resistance to Strong poisoning ability, strong ion bombardment resistance, strong launch ability, different types of magnetic sequences and high neutron absorption coefficient, etc. These superior properties make it widely used in national defense and civil industries, in military, aerospace and other high-tech The field also has broad application prospects, and more and more people pay attention to it. LaB 6 It is an excellent cathode emitting materi...

AI Technical Summary

Problems solved by technology

Since La is easy to oxidize, simple B is expensive, and the burning loss is serious. The operation needs to be carried out in a vacuum or an inert atmosphere. This method requires high equipment and difficult process control.

The boron thermal reduction method is the La 2 o 3 (or LaCl 3 ) and boron powder mixed, high temperature reaction synthesis LaB 6 Powder, because the raw material is high-purity boron powder, so the production cost is high

The principle of carbothermal reduction method is that in La 2 o 3 Add B and C or B to 4 C, then make the mixture into pellets, and heat it in vacuum or argon at 1500°C to 1800°C to obtain LaB 6 , since the raw material adopts high-purity B powder or B 4 C, so the production cost is high and the energy consumption is high

Electrolysis also has the disadvantages of high energy consumption, high cost, and low output

In summary, it can be seen that the traditional preparation of LaB 6 The powder method has the disadvantages of high energy consumption and complicated process.

In recent years, it has been paid more and more attention by researchers. Many foreign researchers have studied this material, but there are few domestic studies.

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