Microstructures and properties of Sn-Ag-Cu lead-free solder alloys containing La
Trace amounts of La were utilized to improve the melting behaviors,microstructures,tensile properties and microhardness of Sn-3.0Ag-0.5Cu lead-free solder alloy.La has little effect on the melting behavior of Sn-3.0Ag-0.5Cu alloy according to the differential thermal analysis (DTA) tests.The X-ray diffraction (XRD) patterns show that β-Sn,Ag3Sn and Cu6Sn5 coexist in the as-cast solder alloys and LaSn3 phases emerge when adding 0.4％ La.The microstructures modified by La are more uniform and much finer than that of baseline alloy,and the coarse LaSn3 particles with complex dendrites are observed by optical microscopy (OM) and scanning electron microscopy (SEM) when the addition of La is up to 0.4％.The composition of the LaSn3 phases is identified by energy-dispersive spectroscopy (EDS).There are considerable improvements in mechanical properties with 0.05％ and 0.1％ addition,but degenerations by adding 0.4％La.The Vickers microhardness of β-Sn and eutectic area are both enhanced with the addition of La and the microhardness of LaSn3 is much larger than those of β-Sn and eutectic area.
lead-free solder Sn-Ag-Cu alloy rare earth element La tensile properties
ZHOU Ying-chun PAN Qing-lin HE Yun-bin LIANG Wen-jie LI Wen-bin LI Yun-chun LU Cong-ge
School of Materials Science and Engineering,Central South University,Changsha 410083,China
国际会议
2007年国际有色金属大会(International Conference of Nonfereous Materials 2007)(ICNFM)
长沙
英文
2007-11-28（万方平台首次上网日期，不代表论文的发表时间）