Sr添加Mg-6Zn-4Si铸态合金的腐蚀行为研究（英文）

发布时间：2018-04-04 17:04

本文选题：镁合金　切入点：铸造　出处：《稀有金属材料与工程》2017年09期

【摘要】：利用XRD、OM、SEM、EDS、极化曲线测试和浸泡试验分析研究Sr元素添加Mg-6Zn-4Si铸态合金的显微结构和腐蚀行为。Sr元素的添加能够有效地改善Mg-6Zn-4Si合金中初生及共晶Mg2Si相的形貌和尺寸。随着Sr元素添加量的增加,初生Mg2Si相的尺寸先降低后逐渐增加。Sr元素能够有效地改善合金的耐腐蚀性。当Sr添加量为0.5%(质量分数)时,合金具有最优的耐蚀性,此时表现为最高的腐蚀电位,最低的腐蚀电流密度和腐蚀速率。添加Sr元素后,细小且分散均匀的Mg2Si相是耐蚀性提高的主要原因。过量的Sr添加会形成针状Sr Mg Si新相,降低了合金的耐蚀性。
[Abstract]:The morphology and size of primary and eutectic Mg2Si phase in Mg-6Zn-4Si alloy were studied by polarization curve test and immersion test. The microstructure and corrosion behavior of as-cast Mg-6Zn-4Si alloy with Sr addition were studied by means of XRD OMSEMN EDS, and the morphology and size of primary and eutectic Mg2Si phase in Mg-6Zn-4Si alloy were improved effectively.With the increase of Sr content, the size of primary Mg2Si phase decreases first and then increases gradually. Sr element can effectively improve the corrosion resistance of the alloy.When the content of Sr is 0.5 (mass fraction), the alloy has the best corrosion resistance, which shows the highest corrosion potential, the lowest corrosion current density and corrosion rate.After the addition of Sr, the small and dispersed Mg2Si phase is the main reason for the improvement of corrosion resistance.The addition of excess Sr can form a new phase of needle-like Sr mg Si and decrease the corrosion resistance of the alloy.
【作者单位】：南京航空航天大学;南京科技职业学院;
【基金】：The Funding of Jiangsu Innovation Program for Graduate Education(CXZZ13_0160) the Fundamental Research Funds for the Central Universities,Nanjing University of Aeronautics and Astronautics Research Funding(NS2013060) the Priority Academic Program Development of Jiangsu Higher Education Institutions
【分类号】：TG172

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