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This paper explores the possibility that flexible fibres of different lengths substitute for sheath to fulfil brush plating from the perspective of optimising solution carrier. SEM, EDS, XRD, TEM, microhardness tester are respectively adopted to study the effects of fibre length on coatings' morphology, structure and hardness. The results indicate that compared with sheath brush plating, fibre length greatly influences morphology, grain size, hardness of coatings. The existence of a large number of grain boundaries and proper defect densities will prevent the dislocation moving, therefore, mechanical properties like hardness of coatings will be improved.

This paper tentatively chooses polyester, bamboo fibre and cotton as solution carrier during the plating process. The morphology, deposition rate, phase structure, hardness, friction and wear properties of coatings is characterised. Water absorbency, heat dissipation and electrical conductivity of three different solution carriers are analysed in order to study their action mechanism. The results show that the bamboo fibre presents the smoothest and compacts surface morphology and good water absorbency, which can ensure the supplement of solution. It also features larger electricity resistance and lower deposition rate, but fine grain, high hardness and good wear-resistance, all of which result in the best comprehensive performance. Cotton, with the best water absorbency, characterises higher hardness but poor uniformity and wear-resistance. Polyester carries the worst water absorbency, fast deposition rate, low hardness and better wear-resistance.

The effects of the codeposition ions on structural and tribological properties of electro-brush plated coatings were investigated. The microstructure and phase structure were studied with scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The hardness and tribological properties of several coatings with different kind of codeposition ions were studied. Results show that among the coatings with different FeCl 2 contents in electrolyte, the Fe400 coating has the best surface property. When proper chemical ion W codeposited with iron ion is added, the hardness of the coatings is improved obviously and the Fe-W II coating has the best properties. When proper element of Cu is added, the hardness and tribological properties of the Fe-W-Cu coatings are also improved. Besides, the interface bond strength between the coating and the substrate is improved obviously, and the Fe-W-Cu II coating has the best properties.