摘要
为了改善铝合金点焊熔核质量,通过添加微量稀土元素Er和Ce形成调质熔核,对熔核微观组织观察和能谱分析的结果表明,熔核区晶粒组织明显细化,在熔核中出现金属间化合物,起到促进形核、细化晶粒和阻碍位错运动的作用.对熔核力学性能测试,采取了一种新型的测试方法—小冲杆试验.结果表明,熔核的硬度和强度提高了10%左右,稀土元素的加入能够通过改变微观组织结构提高铝合金点焊熔核的力学性能,改善熔核质量.
The strength and microstructure characteristics of the nugget in aluminum alloy resistance spot welding were evaluated in this study with and without addition of rare earth elements Er,Ce.The strength was assessed by a small punch test mode and the microstructure was studied with an optical microscope and energy-dispersive spectroscope.Results indicated that the hardness and strength increased about 10% after adding rare earth elements Er,Ce in the nugget.The grain of nugget zone was refined significantly.In the boundary and interior of the grain,a number of intermetallics were dispersed.The intermetallics can not only promote mucleation and refinement,but also hinder the dislocation movement.It was proved that rare earth elements could improve the properties of nugget significantly.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2011年第3期73-76,116-117,共4页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(50975197)
天津应用基础研究计划基金资助项目(09JCZDJC24000)
国家863高技术研究发展计划资助项目(2008AA04Z136)
广东省教育部产学研结合项目(2007A0903021050)
天津高校双五科技计划项目(2009E6-0020)
教育部新世纪人才资助项目
关键词
电阻点焊
铝合金
熔核
稀土元素
小冲杆试验
resistance spot welding
aluminum alloy
nugget
rare earth element
small punch test
