这是旅居加拿大的华裔学者章小鸽博士为美国金属学会主编的新版(2005年)《MetalsHandbook金属手册》编写的一章“Corrosion of Zinc and Zinc Alloys”的中文译文。章博士长期从事锌和锌合金腐蚀的研究和开发,本文全面和系统地介绍了国...这是旅居加拿大的华裔学者章小鸽博士为美国金属学会主编的新版(2005年)《MetalsHandbook金属手册》编写的一章“Corrosion of Zinc and Zinc Alloys”的中文译文。章博士长期从事锌和锌合金腐蚀的研究和开发,本文全面和系统地介绍了国际上目前这一领域的技术和知识状况,突出了镀锌钢材在各个领域的应用。最近几年我国镀锌钢材的生产有几乎爆炸式的发展,2000年全国总共才有13条连续镀锌板生产线,短短几年就上升到140多条。我们认为,本文非常适应当前国内的这一需要,对于我国锌合金镀层的生产和应用会有指导作用。全文经作者授权并由徐乃欣教授翻译,又经作者校阅。本刊分2次连续刊出。展开更多
U-channel forming tests were performed to investigate the surface topography evolvement of hot-dip galvanized(GI) and galvannealed(GA) steels and the effects of die hardness on sheet metal forming(SMF). Experimental r...U-channel forming tests were performed to investigate the surface topography evolvement of hot-dip galvanized(GI) and galvannealed(GA) steels and the effects of die hardness on sheet metal forming(SMF). Experimental results indicate that the surface roughness values of the two galvanized steels increase with the number of forming,i.e.,the surface topographies of galvanized steels are roughened in SMF. Moreover,GI steel has a better ability of damage-resistance than GA steel. The mechanisms of topography evolvement are different in the forming of GI and GA steels. Scratch is the main form of surface damage in the forming of GI steels. The severity of scratch can be decreased by increasing die hardness. GA steel results in exfoliating of the coating firstly and then severe scratching. The surface topography of galvannealed steels can be improved by increasing die hardness. However,the hardness should not be too high.展开更多
The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of ...The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of the coatings were investigated using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),Tafel polarization measurements and neutral salt spray(NSS) tests,and were compared with those of the single coatings. The results show that post-sealing the phosphated HDG steel with molybdate solution,the pores among the zinc phosphate crystals are sealed with molybdate films containing Zn,P,O and Mo,and the continuous composite coatings are formed. The suppression of both the anodic and the cathodic processes of zinc corrosion on the samples are enhanced significantly. The synergistic corrosion protection effect of the single phosphate coatings and molybdate films for zinc is evident. The corrosion resistance of the composite coatings increases with phosphating time up to 300 s.展开更多
文摘这是旅居加拿大的华裔学者章小鸽博士为美国金属学会主编的新版(2005年)《MetalsHandbook金属手册》编写的一章“Corrosion of Zinc and Zinc Alloys”的中文译文。章博士长期从事锌和锌合金腐蚀的研究和开发,本文全面和系统地介绍了国际上目前这一领域的技术和知识状况,突出了镀锌钢材在各个领域的应用。最近几年我国镀锌钢材的生产有几乎爆炸式的发展,2000年全国总共才有13条连续镀锌板生产线,短短几年就上升到140多条。我们认为,本文非常适应当前国内的这一需要,对于我国锌合金镀层的生产和应用会有指导作用。全文经作者授权并由徐乃欣教授翻译,又经作者校阅。本刊分2次连续刊出。
基金Project(50605043) supported by the National Natural Science Foundation of China
文摘U-channel forming tests were performed to investigate the surface topography evolvement of hot-dip galvanized(GI) and galvannealed(GA) steels and the effects of die hardness on sheet metal forming(SMF). Experimental results indicate that the surface roughness values of the two galvanized steels increase with the number of forming,i.e.,the surface topographies of galvanized steels are roughened in SMF. Moreover,GI steel has a better ability of damage-resistance than GA steel. The mechanisms of topography evolvement are different in the forming of GI and GA steels. Scratch is the main form of surface damage in the forming of GI steels. The severity of scratch can be decreased by increasing die hardness. GA steel results in exfoliating of the coating firstly and then severe scratching. The surface topography of galvannealed steels can be improved by increasing die hardness. However,the hardness should not be too high.
基金Project(07BS405) supported by the Excellent Talents Foundation of Huaqiao Univeristy, China
文摘The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of the coatings were investigated using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),Tafel polarization measurements and neutral salt spray(NSS) tests,and were compared with those of the single coatings. The results show that post-sealing the phosphated HDG steel with molybdate solution,the pores among the zinc phosphate crystals are sealed with molybdate films containing Zn,P,O and Mo,and the continuous composite coatings are formed. The suppression of both the anodic and the cathodic processes of zinc corrosion on the samples are enhanced significantly. The synergistic corrosion protection effect of the single phosphate coatings and molybdate films for zinc is evident. The corrosion resistance of the composite coatings increases with phosphating time up to 300 s.
