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目的：研究热镀锌板表面平均粗糙度Ra和峰值数Rpc对无铬耐指纹热镀锌板表面耐指纹性、耐腐蚀性和涂装性的影响。方法将Ra=0.6~1.1μm和Rpc=55~100的热镀锌板制成耐指纹板,采用X射线光电子能谱仪分析其组成,采用分光光度仪分析其耐指纹性,采用硫酸铜混合溶液滴定和盐雾试验方法检测其耐腐蚀性,采用涂漆和冲击实验检测其涂装性。结果耐指纹膜和锌层表面形成Si—O—Zn金属键,耐指纹膜除了物理结合,还通过化学键合的方式与锌层表面结合。在充分交联固化和化学键合的情况下,无铬耐指纹热镀锌板耐指纹性不受热镀锌板Ra和Rpc的影响；热镀锌板Ra值越低,耐腐蚀性越好；耐指纹膜单位质量为1.1 g/m2,Ra≤1.1μm时,耐指纹板72 h盐雾试验白锈面积不大于5%；热镀锌板Rpc值越高,无铬耐指纹热镀锌板涂装性越好,Rpc≥80时,耐指纹热镀锌板涂漆冲压后,漆膜完好。结论 Ra和Rpc对热镀锌板耐指纹性影响不大,对耐磨蚀性和涂装性影响显著。

ABSTRACT:Objective To investigate the effects of average roughness ( Ra) and peak count ( Rpc ) on fingerprint resistance, corrosion resistance and paint adhesion of Cr-free anti-fingerprint hot-dip galvanized steel sheets. Methods The anti-fingerprint steel sheets were made in lab, using hot-dip galvanized steel sheets with various Ra(0. 6~1. 1 μm) and Rpc(55~100) values. The composition of the coatings was investigated by X-ray photoelectron spectroscopy ( XPS) . The fingerprint resistance of anti-fin-gerprint sheets was tested with spectrophotometer. The corrosion resistance of sheets was tested by CuSO4 titration and salt spray tests. The paint adhesion of sheets was tested by painting and impacting tests. Results The results showed that Si—O—Zn metal bond formation reaction occurred between anti-fingerprint coating and zinc coating which bonded by physical and chemical bonding. Ra and Rpc of the hot-dip galvanized steel sheets had no effect on the fingerprint resistance of the anti-fingerprint sheets with full crosslinking-solidification and chemical bonding. Lower Ra of hot-dip galvanized steel sheets led to higher corrosion resistance for anti-fingerprint sheets. Area of white rust on anti-fingerprint sheets after 72 hours salt spray tests was greater than or equal to 5%when Ra≤1. 1 μm and coating weight was 1. 1 g/m2 . Higher Rpc of hot-dip galvanized steel sheets led to better paint adhesion for anti-fingerprint sheets. Paint adhesion of anti-fingerprint sheets was satisfactory when Rpc≥80. Conclusion The effects of Ra and Rpc is less on the finer resistance and is important on the corresion resistance and paint adhesion.