冷却条件和Ce含量对Galfan合金凝固组织及其耐蚀性的影响  

Solidification Microstructure and Corrosion Resistance of Galfan Alloy with Different Cooling Conditions and Ce Content

作　　者：杨廷志[1] 吴长军[1] 王建华[1] 刘亚[1] 涂浩[1] 苏旭平[1] 

机构地区：[1]常州大学江苏省材料表面科学与技术重点实验室,江苏常州213164

出　　处：《稀有金属》2015年第7期583-588,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51201023);江苏省高校自然科学研究项目(12KJB430002)资助

摘　　要：Galfan合金中的稀土元素对合金的组织和耐蚀性有显著影响。实验研究了稀土元素Ce含量(质量分数)分别为0,0.05%,0.10%和0.20%的Zn-5%Al-x Ce合金在炉冷、空冷和水冷3种冷却条件下的凝固组织及其耐蚀性,进而分析稀土元素添加量和冷却方式对Galfan合金显微组织及耐蚀性的影响。结果表明,冷却条件和Ce含量对Zn-5%Al-x Ce合金的显微组织和耐蚀性有明显影响。随Ce含量的增加,Zn-5%Alx Ce合金的层片共晶组织分布均匀,杂质、裂纹等缺陷减少。Ce元素的加入显著改善了合金的凝固组织和耐蚀性,使合金的耐蚀性先增强后减弱。此外,合金的冷却速度越大,获得的组织越致密,且耐蚀性越好。Zn固溶体呈完整树枝状,棒状,胞枝状到胞状变化。研究认为,添加0.1%Ce的Galfan合金水冷后的耐蚀性最好。The microstructure and the corrosion resistance of Galfan alloys were significantly affected by existence of rare earth elements. In the present work,0,0. 05%,0. 10% and 0. 20%（ mass fraction） Ce,respectively,were added into the Zn-5% Al alloy,and the effects of rare earth contents and cooling method on microstructure and corrosion resistance of Galfan alloys were investigated.All of the alloys were cooled by three kinds of methods,furnace cooling,air cooling and water cooling. Then the microstructure and the corrosion resistance were examined. Experimental results indicated that cooling conditions and Ce content had a significant effect on the microstructure and corrosion resistance of Zn-5% Al-x Ce alloys. With the increase of Ce content,the amounts of defects decreased and its eutectic structure was improved. The addition of Ce significantly improved the microstructure and the corrosion resistance of Galfan alloys. However,the corrosion resistance of alloys was enhanced firstly and then weakened. Besides,the eutectic structure became denser and the corrosion resistance became much better with the increase of cooling rate. Zn solid solution changed from full dendritic,rod,cell-dendritic to cellular. It was believed that Galfan alloy with the best corrosion resistance could be obtained when 0. 10% Ce was added with water cooling.

关 键 词：GALFAN合金 凝固组织 共晶组织 耐蚀性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]