Preparation method of ultrafine metal powder

Abstract

The invention relates to a preparation method of ultrafine metal powder, which belongs to the field of material preparation. The preparation method specifically comprises the steps of smelting, atomizing, cooling, depositing, drying and grading, wherein deoxidation treatment is performed in a smelting process. According to the preparation method, the degree of oxidation is reduced by adding a deoxidation covering agent in the smelting process, so that nonmetallic inclusions and fine refractory particles in smelting liquid can be effectively adsorbed so as to purify the smelting liquid. Additionally, the injecting speed of atomizing gas can be increased by using a laval nozzle in an atomizing process, laminar atomizing airflow at 2.5 to 5 times supersonic speed can be formed under 0.2 MPa, the phenomenon that ultrafine alloy is aggregated can be effectively inhibited by the laminar atomizing airflow, ultrafineness of the metal powder can be realized, and the rate of finished products of the ultrafine metal powder is greatly increased.

Description

Technical field [0001] The invention relates to the field of material preparation, in particular to a method for preparing ultrafine metal powder. Background technique [0002] The ultra-fine metal powder has small size and large specific surface area. The metal parts made with it have many properties different from conventional materials, such as relatively excellent mechanical properties, special magnetic properties, electrical conductivity and diffusivity, and high Reactivity and catalytic activity. These special properties make ultrafine metal powder materials more and more used in aerospace, metallurgy, chemical and other fields. [0003] At present, the methods for preparing ultrafine metal powder mainly include ball milling, jet milling, plasma rotating electrode method, physical chemical method, and gas atomization method. [0004] Among them, the gas atomization method is one of the main methods for producing ultrafine metal and alloy powders. The basic principle of gas a...

AI Technical Summary

Problems solved by technology

The current gas atomization method uses gas for atomization in the atomization stage. Since the current gas injection equipment is a direct-injection tube body, the gas flow rate is low to a certain extent, resulting in the prepared metal or The particle size of the alloy powder is relatively coarse, and the preparation of finer powder must be pressurized, even if the powder particle size produced by pressurizing in the tube body has a low yield

[0005] Moreover, in the prior art, when smelting metals or alloys, the control of the purity of the metals or alloys cannot be optimized, which directly leads to the situation that the purity of the prepared ultrafine metal powder cannot be achieved, and contains more Multiple impurities

In the general traditional metallurgical process, it is the most effective technology to add a covering agent on the solution surface after smelting, but almost all covering agents are added to the solution surface in the tundish after smelting , and as we all know, smelting itself is a process, and the generation of impurities is also produced during smelting, and in the smelting process, the smelting liquid is prone to reduction and oxidation reactions with the refractory material layer, so that the Si in the smelting liquid exceeds the standard and generates a large amount of Al. 2 o 3 Inclusions, leading to contamination of the smelting liquid

Images