| Mechanical plating technology can plate other metals on the surface of steel, so the surface can obtain other metallic properties. Currently steel parts were mechanically plated single metal, such as zinc coating, and only use mixed powder of different single-metal to plate alloy coating, the internal coating performance varied. In addition, deposition boost agent composition and process parameters have no quantitative research, so that the properties of the mechanical plating can not play its importance, which hindered the application of the technology in the field of surface engineering. In order to solve these problems, the paper first directly use Cu-Zn alloy powder of uniform characteristic to prepare coating. The research of this paper includes composition of deposition boost agent, alloy powder property impact on the layer, optimization of process parameters, micro-structure and layer forming process analysis and so on.It was unable to directly use mechanical plating zinc deposition accelerator. Considering the experience of mechanical zinc plated steel parts and material properties of Cu-Zn alloy, orthogonal test was used to optimize deposition agent composition. Steel alloy coating surface quality improved to a certain extent. On the basis of the successful preparation of mechanical plated Cu-Zn alloy coating, single factor variable experimental methods was used to study alloy powder composition, particle size and plating process parameters effect on the appearance of the coating, the coating porosity, coating density, micro-hardness, coating bond strength and corrosion resistance of the coating under acidic environment. After the experiment, SEM and EDS was used to analyze the coating phase composition and observe coating micro-structure morphology. In addition, the coating adhesion and the layer forming process was analyzed. The results are as follows:1.The optimal deposition agent composition after orthogonal experiments include:15% polyethylene glycol 400,6% OP-10,0.5% bentonite,0.8% celite,7% monoammonium phosphate,1.5% sodium gluconate,40% stannous salt. Alloy coatings prepared at this time has the best overall performance.2.The composition of the alloy powder mainly affects the coating hardness and corrosion resistance, with the increase of alloy powder Cu element content, the surface hardness will decline, while the corrosion resistance will increase. The particle size of the alloy powder mainly influence coating bond strength and corrosion resistance. Coating prepared by 1200 mesh alloy powder has best combination strength and corrosion resistance.3.Glass bead ratio of 3:1:1 and the 1.4 times loading amount of glass beads can obtain best coating adhesion strength. When the barrel plating line speed was 50r/min and 60r/min, the intensity was level 1. When the strengthen time was 15 minutes, alloy coating surface was sharp and micro-hardness was 38.48 HV0.2.4.Mechanical engagement exists within the coating improve the bonding strength of the coating. The composition change is consistent of the plating process sequence. Internal bond strength of the coating consists the mechanical bonding force, van der Waals force, and chemical bonding force. Coating formation process did not occur on atomic structure level, it’s no crystalline layer forming process. |
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