| The practical application of Fe-Al intermetallic compound is limited by its brittleness and shape-forming difficulty at room-temperature, which promoted the development of many kinds of aluminizing processes such as high velocity arc spraying technology, laser cladding technology, plasma spraying technology, etc. However the results show that the traditional aluminizing processes exist still some shortcomings presently. For example it is rough on surface of the aluminized layers prepared by those processes and the adhesive force between the aluminized layers and substrate are lower. Therefore, the paper puts forward the research on preparation of Fe-Al alloy layer on 45 steel by double-glow plasma alloying.The technology and mechanism of this kind of aluminizing process had been studied, and optimization design was made on the parameters of this process. Finally, microstructure, component distributing and phase, hardness and bonding strength, corrosion and wear performance of Fe-Al alloy layer were also studied. The results show that the thickness of Fe-Al alloy layer is up to 324μm. Its surface is relatively smooth and the adhesive force with matrix is fine because of metallurgical binding. Component possesses gradient distribution along the depth of the layer. Fe-Al alloy layer is mainly composed of FeAl, Fe3Al andα-Fe(Al). In the Fe-Al alloy layer, the hardness of deposition layer can be higher, but it's lower in diffusion layer and decreases along the depth of the layer. Meanwhile, the layer has good corrosion resistance both in 2.0%Na2S solution and 0.05mol/L Na2SO4+0.5mol/L NaCl solution. Moreover, wear-resistant of the layer is excellent at elevated temperatures.
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