生长速率的影响
(哈尔滨理工大学 材料科学与工程学院，哈尔滨 150040)
摘 要: 通过加速温度时效方法研究Ni和Bi元素对低银 (含银量小于1%，质量分数) Sn-Ag-Cu（LASAC）钎料界面IMC生长速率的影响。通过与高银钎料SAC305和低银钎料LASAC对比，分析添加Ni和Bi元素后LASAC钎料在高温时效过程中热疲劳抗性的变化情况。结果表明：LASAC/Cu、LASAC-Bi/Cu和 SAC305/Cu界面IMC时效后均形成较厚的Cu3Sn层，LASAC-Ni/Cu界面经IMC时效后则形成较薄的(Cu, Ni)3Sn；高银钎料SAC305在180 ℃时效下IMC生长速率为2.17×10−5 μm2/s，与之相比，低Ag钎料LASAC IMC在时效过程中生长速率较高，为3.8×10−5 μm2/s；Ni和Bi元素的添加均可降低钎料LASAC/Cu界面IMC的生长速率，其中Bi的改善效果最显著，LASAC-Bi钎料的IMC生长速率为1.92×10−5 μm2/s，低于SAC305钎料的IMC生长速率。
关键字: 生长速率；界面化合物(IMC)；高温时效；低银钎料
（School of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China）
Abstract:The effects of Ni and Bi addition on the intermetallic compound (IMC) growth rate of low-Ag (＜1%, mass fraction) Sn-Ag-Cu(LASAC) soldering were investigated by accelerated temperature aging. The thermal fatige resistance of LASAC solders with Ni and Bi addition was studied by comparing with SAC305 solder. The results show that thick Cu3Sn layer forms after high temperature storage (HTS) aging between LASAC/Cu, LASAC-Bi/Cu and SAC305/Cu interfaces. While the IMC between LASAC-Ni/Cu is (Cu, Ni)3Sn layer with a very thin thickness after aged. The IMC growth rate of SAC305 is 2.17×10−5 μm2/s. However, the IMC growth rate of LASAC solder is 3.8×10−5 μm2/s, which is faster than that of SAC305. The growth rate of IMC at LASAC/Cu interface decreases with Ni and Bi addition. Bi shows a better improvement for solder compared with Ni element. The IMC growth rate of LASAC-Bi is 1.92×10−5 μm2/s, which is slower than the IMC growth rate of SAC305.
Key words: growth rate; intermettalic compound (IMC); high temperture storage aging; low-Ag solder
