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。
The microstructure and corrosion resistance of Mg-6Zn-4Si alloy with Sr addition were studied using XRD,OM,SEM,EDS,potentiodynamic polarization and immersion testing. The results show that the morphologies and sizes of both the primary and eutectic Mg2 Si in Mg-6Zn-4Si alloy can be effectively modified by the Sr additions. With the increasing amount of Sr addition,the primary Mg2 Si phase experiences a decrease in the grain size with a subsequent increase. Sr significantly improves the corrosion resistance of Mg-6Zn-4Si alloy. The ternary alloy with 0.5wt%Sr has the optimal corrosion resistance,which exhibits the highest corrosion potential,the lowest corrosion current density and corrosion rate. The homogeneous dispersion of fine Mg_2Si particles with Sr element is responsible for the improvement of corrosion resistance. Excessive Sr（≥1.0wt%） leads to the generation of Sr Mg Si new phase,which has unfavorable effects on the corrosion resistance of the alloys.
作者
丛孟启
李子全
刘劲松
王梦慧
盛备备
王碧军
Cong Mengqi Li Ziquan Liu Jinsong Wang Menghui Sheng Beibei Wang Bijun(Nanjing University ofAeronautics andAstronautics, Nanjing 210016, China Nanjing Polytechnic Institute, Nanjing 210048, China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2017年第9期2405-2410,共6页
Rare Metal Materials and Engineering
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
关键词
镁合金
铸造
显微结构
腐蚀行为
magnesium alloys
casting
microstructure
corrosion behavior
