Research Of Ultrasonic-based Wet Mechanical Zn-Al Coating

Mechanical plating is one kind of the surface treatment technology which is clean and environmental,and it is obtained widely used in the industrial manufacture.The mechanical plating technology can only used for the sub-size parts as well as the cover coating is unitary,and the quality of coating decay resistance notas well as the alloy coating.Hence,on the based of Wet ultrasonic mechanicalzinc coating,5% aluminite powder is added by the zinc powder.Wet ultrasonic mechanical galvanizing-aluminum alloy coating was obtained by mean of the self-developed device.This paper mainly analyzed the activation and sedimentary rule of the metal powder in the process Coating formation.The surface of the coating and the fracture appearance was analyzed by the scanning electron microscope.Metallographic surface morphology of coating was observed and analyzed with the metallographic microscope.The thickness of the coating,the adhesive strength and the coating porosity were tested by the device of thickness tester,Row lattice unit and the way of sticking the paper.The clad layer’s corrosion resistance is tested with the method of neutral salt spray test and bubble was full etching experiments.Meanwhile,clad layer’s Phase characteristics,the distribution and content of element were analyzed by the device of the electron microscope EDS module,and x-ray diffract meter.The test result indicated that workpiece’s surface was complete covered by the Zinc – aluminum powder,as well as the workpiece’s color uniformity and without missing plating place.The workpiece surface had no obviously flaw such as peeling and bubble phenomenon.The workpiece’s Zinc layer’s color covered by the method of Wet ultrasonic mechanical galvanizing was whiter than Zinc layer was covered with the method of Wet ultrasonic mechanical plating.Wet ultrasonic mechanical galvanizing-aluminum’s layer surface was composed by the plate area flat area and the two areas were contact closely to each other.The particle of the zinc powder(or aluminize powder)in the clad layer stick to each other to form the whole body,zinc powder’s and the aluminize powder’s size was bigger than the original’s.Between the thickness of Wet ultrasonic mechanical galvanizing – aluminum and the thickness of the set existed a certain deviation.The clad layer’s porosity was Low,the density is high,bonding strength was good as well as corrosion resistance was good.The indication come from the coating composition and the phase analysis was known that the aluminum,zinc,iron,tin and the metals were existed by the form of simple substance,meanwhile there was no new phase generate also the content of aluminum was very low and the content’s level was between 3% an d 5%.The aluminum layer gathered in the process of the formation and the compact oxidation film was formed on the surface of aluminum made the corrosion resistance of coating got significantly improved.