微量锑和锡对铝基牺牲阳极材料性能的影响

Effect of Sb and Sn on performance ofaluminum sacrificial anode materials

熔炼了添加合金元素Sb和Sn的5种Al2Zn2In系牺牲阳极材料,采用恒电流方法测试了其电化学性能,采用金相显微镜、扫描电镜和能谱分析分别观察和分析了阳极材料的显微组织和组成。结果表明:Sb具有细化晶粒的作用,但晶界存在较多偏析相,电流效率偏低;与Sb相比较,Sn也具有细化晶粒的作用,电流效率有所提高,晶界偏析相较少,但阳极的表面腐蚀溶解不均匀;Sn和Sb的协同作用在于能有效地抑制Si的偏析,显著提高阳极的电流效率,使得阳极表面具有良好的腐蚀溶解性。

Five kinds of Al-Zn-In system sacrificial anode materials with different contents of Sb and Sn were cast. The electrochemical performance was tested with constant current method and microstructures were observed and analyzed by metallography microscope, scanning electron microscope and energy spectrum analysis. The results show that Sb addition can diminish the crystal grain, but the content of segregative phase at crystal boundary increases, and the current efficiency of material is low. Compared with Sb addition, Sn addition can also diminish the crystal grain, the current efficiency increases, the content of segregative phase at crystal boundary reduces, but diffusional corrosion of the anode surface is not uniform. The cooperation of Sb and Sn can prevent Si from segregating effectively and enhance the current efficiency obviously. At the same time, anode materials have preferable surface dissolution characteristics.