碳钢表面Zn-Al合金渗层的制备及性能研究

Preparation and Property Study of Zn-Al Alloy Layers on Surface of Carbon Steel

采用固体粉末渗入法在20钢表面制备Zn-Al合金渗层。对比分析了Zn-Al渗层和20钢的显微硬度、耐磨性及耐蚀性。结果表明：温度控制在450~460℃,Zn含量为50%,Al含量为20%,渗入时间4 h,Zn-Al渗层厚度可达45μm;Zn-Al渗层主要相由Al Fe、Fe Zn10.98、Fe Zn8.87和Fe Zn6.67、Fe3Zn10等构成;其显微硬度可达325 HV,高于20钢的硬度（180 HV）;Zn-Al渗层与钢球（GCr15）对磨的平均摩擦系数为0.1878,磨损失重为0.0010 g,较20钢的分别降低了38%和43%;Zn-Al渗层具有较好的耐盐雾腐蚀性能,经48 h中性盐雾实验后无红锈出现,电化学测试显示Zn-Al渗层腐蚀电流较20钢的更小,Zn-Al合金渗层可以对20钢基体进行有效的防腐和耐磨防护。

Zn-Al alloy layer was prepared by solid powder permeating motod on the surface of the 20 steel matrix. The micro-hardness,wear resistance and corrosion resistance of Zn-Al layers and 20 steel were compared and analyzed. The results show that it is controlled the temperature at 450 ~ 460 ℃,the content of Zn at 50%,the content of Al at 20%,the treatment time for 4 h,the thickness of Zn-Al layers is up to45 μm,then Zn-Al layers is mainly composed of Al Fe,Fe Zn10. 98,Fe Zn8. 87,Fe Zn6. 67 and Fe3Zn10 phases and the its micro-hardness is up to 325 HV,which is higher than the 20 steel substrate（ 180 HV）.The average friction coefficient is 0. 1878 as Zn-Al layers and steel ball（ GCr15） for grinding and the weight loss is 0. 0010 g,which are decreased by 38% and 43% respectively compared with 20 steel. The Zn-Al layers have good corrosion resistance and do not rust after salt spray corrosion for 48 h. Electrochemical test shows that the corrosion current of Zn-Al layers is smaller than the 20 steel,and Zn-Al alloy layers can provide effective protection for corrosion resistance and wear resistance of 20 steel substrate.