Preparation of Fe/Cu Bimetallic Powders by Direct Substitution Reaction
Abstract:
The Fe/Cu bimetallic powder was synthesized by substitution reaction with copper sulfate and reduced iron powder as the main raw materials.The influence of a kind of addition agent, the reaction time, and the drying and reduction process on the properties of the powder was investigated by X-ray diffraction and scanning electron microscope.Oxidation resistance of the powders was tested by impulse heating-infrared absorption method and temperature and humidity simulation method.The experimental results showed that Fe particles were coated with Cu coating in the Fe/Cu bimetallic powder, and the thickness of the coating was about 1 μm.The addition agent was in favor of forming compact coating.The reaction time ranged from 25 to 30 min.The proper drying and reduction conditions were that the reduction temperature was between 500 and 650 ℃, and the reduction time was between 2 and 3 h, and the highest of metal yield rate was 99.5%.The oxidation of Fe/Cu bimetallic powder was effectively to prevented after adding a kind of antioxidant.The Fe/Cu bimetallic powder were made of Cu phase and Fe phase, the copper content in which was 19.53%.Moreover, a new method about treatment of the large amount of FeSO4 supernatant liquor was put forward.The FeSO4 supernatant liquor could be used as the raw materials of ultra fine Fe-based pre-alloyed powders for diamond tools.The new method had advantages of simplicity, rationality, low cost, environment protection and high added value.
Fig.2 Effect of a kind of addition agent on the microstructure of Fe/Cu bimetallic powders (a) Without addition agent; (b) Mixing addition agent; (c) Mixing addition agent
表1 反应时间与上清液Cu2+浓度及金属收得率关系
Table 1 Relationships of the reaction time, Cu2+concentration of the supernatant liquor and metal yield rate
Reaction time/min
15
17
20
23
25
27
30
Cu2+ concentration of the supernatant liquor/ (g·L-1)