A kind of low temperature plasma nitriding preparation method of ferronitride magnetic powder

Abstract

The invention relates to a low-temperature plasma nitriding preparation method of iron nitride magnetic powder. The invention uses atomized iron powder, hydroxyl iron powder or reduced iron powder with an average particle size of 2-80 μm as the raw material; feeds O2 and oxidizes at 300-400 °C for 1-10 hours to obtain iron oxide powder; feeds hydrogen, Restore at 300~400°C for 4-20h to regain iron powder; low-temperature plasma nitriding, control temperature at 120~200°C, nitriding for 1~30h; cool down, cool to room temperature with the furnace, and take out the sample. The method uses low-temperature nitrogen plasma for nitriding, which solves the bottleneck problem of low ammonia gas decomposition efficiency in the ammonia gas nitriding method, and effectively improves the nitriding efficiency.

Description

technical field

[0001] The invention relates to a low-temperature plasma nitriding preparation method of iron nitride magnetic powder, which belongs to the field of material preparation. Background technique

[0002] The excellent soft magnetic properties, oxidation resistance and wear resistance of Fe-N compounds make them ideal materials for magnetic recording media and magnetic sensing elements, and have attracted people's attention. Fe-N compounds are mainly Fe 3 N,Fe 4 N and α"-Fe 16 N 2 Wait for a few. According to domestic and foreign literature reports, α"-Fe 16 N 2 The magnetism of iron and nitrogen compounds is the best one, its saturation magnetization reaches 280emu / g, which is higher than that of pure iron, and it is the material with the highest saturation magnetization found so far.

[0003] Due to α"-Fe 16 N 2 The phase is a metastable phase at room temperature, and its formation area is very narrow, so it is necessary to prepare α"-Fe 16 N 2 is a ...