摘要
研究微量稀土钇对AZ91合金微观组织、力学性能、腐蚀性能的影响,考察钇在合金中所形成的稀土相组成和形貌。结果表明,钇在AZ91合金中生成Al4MgY相,可起非均质形核作用,减少二次枝晶间距,细化枝晶组织。加入钇后,合金腐蚀性能得到明显改善,由严重的全面腐蚀向只有表面部分位置有轻微点蚀的均匀腐蚀转变。当钇加入量为1.25%时,合金的室温和高温力学性能最好,分别为264.8MPa和164.8MPa。
The effects of yttrium on the microstructure, mechanical property and corrosion property of AZ91 were studied, the phase composition and microstructure of yttrium in the alloy was also investigated. The results show that yttrium generates A14 MgY phase in AZgl alloy and refines the crystal grain by heteroge-neous nucleation and reducing the secondary dendritic crystal distance. The surface of alloy changes from severe corrosion to uniform corrosion with slight pitting corrosion after adding yttrium. The optimum me- chanical property at room temperature and 200 ℃ are improved to 264. 8 MPa, 164. 8 MPa respectively when the content of yttrium is increased to 1.25 %.
出处
《有色金属(冶炼部分)》
CAS
北大核心
2012年第10期50-54,共5页
Nonferrous Metals(Extractive Metallurgy)
基金
广西自然科学基金项目(2011GXNSFC018005)
广西教育厅自治区级教师教育学科教学团队项目经费资助(桂教师范[2011]84号)
关键词
AZ91镁合金
钇
微观组织
力学性能
腐蚀性能
AZ91 magnesium alloy
yttrium
microstructure
mechanical property
corrosion property