5-2 Microstructures and key properties of mechanical-deposited Zn-Al coatings
Mechanical plating, a room-temperature method that uses kinetic energy to deposit metal coatings on parts, is a relatively cleanly coating process by which coatings can be produced without significant heating of the deposited powder and electric deposition in electroplating. In contrast to the well-known thermal spray processes such as flame, arc, and plasma spraying, in mechanical plating there is no melting of particles prior to impact on the steel substrate. The adhesion of metallic powders in this process is due to their kinetic energy upon impact and internal electrolysis. In this paper, Zinc and aluminum powders was used to deposit coating by mechanical plating. The microstructure of the deposited coating was characterized by optical microscopy (OM), associated with materials workstation version V3. 3. 1, scanning electron microscopy (SEM), equipment with an energy-dispersive X-ray spectroscopy (EDS) analyzer. The results shows that mechanically deposited zinc-aluminum coatings consist of almost the spherically shaped zinc particles mechanically point contacting engaged with each other. The coatings are composed of zinc particles, aluminum particles, interstice, tin production and others, in the coatings, inclusions were detected, which are composed of Fe and Sn. Extra fine zincs and some smaller interspersed inclusions are positioned in the interstices. Thickness measurements revealed that the coatings lacked uniformity, with an uneven thickness distribution and an average variation of approximately 2~5μm. The porosity test shows that porosity was present in the coatings, but this was not interconnected. The adhesion strength test shows that adhesion was good for the coatings, with no samples failing the set test. Salt spray test shows that corrosion resistance of the coatings is better than the mechanically plated zinc coatings with same thickness.
Mechanical plating Zinc-aluminum coatings Microstructure Thickness Porosity Adhesion strength Corrosion resistance
Wang ShengminA He Mingyi Zhao Xiaojun Liu Li Peng Zenghua
Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunm Faculty of Chemistry and Biotechnology, Yunnan Nationalities University, Kunming China
国际会议
第七届亚太镀锌大会(The 7th Asia Pacific General Galvanizing Conference)(7th APGGC)
北京
英文
229-236
2007-09-14（万方平台首次上网日期，不代表论文的发表时间）