挤压处理与Ca添加对Mg-7Sn合金显微组织与耐蚀性的影响  

Effects of Extrusion Treatment and Calcium Addition on the Microstructure and Corrosion Resistance of Mg-7Sn Alloy

作　　者：李万东 黄丽丽 王兴华 LI Wandong;HUANG Lili;WANG Xinghua(Hebei Petroleum University of Technology,Chengde 067000,China;Chengde College of Applied Technology,Chengde 067000,China)

机构地区：[1]河北石油职业技术大学,承德067000 [2]承德应用技术职业学院,承德067000

出　　处：《腐蚀与防护》2023年第7期46-51,共6页Corrosion & Protection

基　　金：基承德市科学技术研究与发展计划项目(202103B011)。

摘　　要：利用金相显微镜(OM)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、电化学试验与浸泡试验等研究了挤压处理与添加合金元素Ca对Mg-7Sn合金显微组织、耐蚀性及力学性能的影响。结果表明:添加Ca元素可以明显细化铸态Mg-7Sn合金的晶粒,并在晶粒内部与晶界形成了棒状的CaMgSn相,同时,腐蚀过程中,添加Ca会使合金表面形成含Ca的化合物,阻止或延缓腐蚀的进行,提高合金的耐蚀性。挤压处理使得合金的平均晶粒尺寸由55.2μm减小到3.3μm,粗大棒状的CaMgSn相被破碎成细小的块状。挤压处理后Mg-7Sn-1Ca合金的耐蚀性出现轻微下降,但保证了较高的显微硬度。挤压态Mg-7Sn-1Ca合金兼具力学性能和耐蚀性。The effects of extrusion treatment and addition of alloying element Ca on the microstructure,corrosion resistance and mechanical properties of Mg-7Sn alloy were studied by optical microscopy(OM),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),electrochemical test and immersion test.The results showed that the addition of Ca element could significantly refine the grains of the cast Mg-7Sn alloy,and form rod-shaped CaMgSn with grain boundaries within the grains.At the same time,during the corrosion process,the addition of Ca could form compounds containing Ca on the alloy surface,prevent or delay corrosion,and improve the corrosion resistance of the alloy.The extrusion treatment reduced the average grain size of the alloy from 55.2μm to 3.3μm,and the coarse rod-shaped CaMgSn phase was broken into small blocks.After extrusion treatment,the corrosion resistance of Mg-7Sn-1Ca alloy slightly decreased,but high microhardness was ensured.The extruded Mg-7Sn-1Ca alloy exhibited both good mechanical properties and corrosion resistance.

关 键 词：Mg-7Sn合金 Ca添加 挤压处理 显微组织 耐腐蚀性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]