研究了稀土Y变质(0%~0.8%,质量分数)对Mg-5Sn-1Si合金显微组织的影响。通过XRD和SEM分析了该合金的组织和相组成。结果表明,受成分过冷的作用,适量Y能有效细化铸态组织。随着Y含量从0.2%增加到0.8%,生长抑制因子GRF值从Mg-5Sn-1Si-0.2Y...研究了稀土Y变质(0%~0.8%,质量分数)对Mg-5Sn-1Si合金显微组织的影响。通过XRD和SEM分析了该合金的组织和相组成。结果表明,受成分过冷的作用,适量Y能有效细化铸态组织。随着Y含量从0.2%增加到0.8%,生长抑制因子GRF值从Mg-5Sn-1Si-0.2Y的16.94增大到Mg-5Sn-1Si-0.8Y的17.96,枝晶臂间距平均尺寸从不含Y的Mg-5Sn-1Si合金的23.7μm减小至Mg-5Sn-1Si-0.8Y合金的12.5μm,减小了约47%。由于Y元素在Mg2Si表面的偏聚,Mg-Y二元相或是Mg-Si-Y三元相将在Mg2Si和α-Mg前沿析出,抑制了共晶Mg2Si的异向生长,使复杂汉字状的Mg2Si转变为棒状组织。当Y含量达到0.8%时,Y元素对Mg2Si变质效果最佳。通过XRD和SEM分析了该合金的相组成,合金由α-Mg基体、Mg2Sn、Mg2Si和少量的Mg24Y5和Mg Si Y组成。使用CASTEP软件包基于第一性原理,计算了三种Mg Si Y晶胞结构的结合能Ecoh,计算结果与Mg2Si结合能的对比,证实了Mg Si Y存在的可能性。展开更多
The formation and the growth of Cu-Sn intermetallic compound (IMC) layer at the interface between Sn-3.0Ag-0.5Cu-xCe solder and Cu substrate during soldering and aging were studied. The results show that Cu6Sn5 IMC is...The formation and the growth of Cu-Sn intermetallic compound (IMC) layer at the interface between Sn-3.0Ag-0.5Cu-xCe solder and Cu substrate during soldering and aging were studied. The results show that Cu6Sn5 IMC is observed at the interface between solder and Cu substrate in all conditions. After aging for 120 h,the Cu3Sn IMC is then obtained. With increasing aging time,the scalloped Cu6Sn5 structure changes to a plate structure. The Cu3Sn film always forms with a relatively planar interface. By adding a small amount of the rare earth element Ce (only 0.1%,mass fraction) into the Sn-3.0Ag-0.5Cu solder alloy,the growth rate of the Cu-Sn IMC at the interface of solder alloy system is decreased. When the time exponent is approximately 0.5,the growth of the IMC layer is mainly controlled by a diffusion over the studied time range.展开更多
文摘研究了稀土Y变质(0%~0.8%,质量分数)对Mg-5Sn-1Si合金显微组织的影响。通过XRD和SEM分析了该合金的组织和相组成。结果表明,受成分过冷的作用,适量Y能有效细化铸态组织。随着Y含量从0.2%增加到0.8%,生长抑制因子GRF值从Mg-5Sn-1Si-0.2Y的16.94增大到Mg-5Sn-1Si-0.8Y的17.96,枝晶臂间距平均尺寸从不含Y的Mg-5Sn-1Si合金的23.7μm减小至Mg-5Sn-1Si-0.8Y合金的12.5μm,减小了约47%。由于Y元素在Mg2Si表面的偏聚,Mg-Y二元相或是Mg-Si-Y三元相将在Mg2Si和α-Mg前沿析出,抑制了共晶Mg2Si的异向生长,使复杂汉字状的Mg2Si转变为棒状组织。当Y含量达到0.8%时,Y元素对Mg2Si变质效果最佳。通过XRD和SEM分析了该合金的相组成,合金由α-Mg基体、Mg2Sn、Mg2Si和少量的Mg24Y5和Mg Si Y组成。使用CASTEP软件包基于第一性原理,计算了三种Mg Si Y晶胞结构的结合能Ecoh,计算结果与Mg2Si结合能的对比,证实了Mg Si Y存在的可能性。
基金Project(06GK2002) supported by the Major Project of Hunan Provincial Science and Technology Development Strategy
文摘The formation and the growth of Cu-Sn intermetallic compound (IMC) layer at the interface between Sn-3.0Ag-0.5Cu-xCe solder and Cu substrate during soldering and aging were studied. The results show that Cu6Sn5 IMC is observed at the interface between solder and Cu substrate in all conditions. After aging for 120 h,the Cu3Sn IMC is then obtained. With increasing aging time,the scalloped Cu6Sn5 structure changes to a plate structure. The Cu3Sn film always forms with a relatively planar interface. By adding a small amount of the rare earth element Ce (only 0.1%,mass fraction) into the Sn-3.0Ag-0.5Cu solder alloy,the growth rate of the Cu-Sn IMC at the interface of solder alloy system is decreased. When the time exponent is approximately 0.5,the growth of the IMC layer is mainly controlled by a diffusion over the studied time range.
