摘要
The microstructures and properties of the Zn-Cu-Bi-Sn(ZCBS) high-temperature solders with various Sn contents were studied using differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and X-ray diffraction(XRD).The results indicate that the increase of Sn content can both decrease the melting temperature and melting range of ZCBS solders and it can also effectively improve the wettability on Cu substrate.The shear strength of solder joints reaches a maximum value with the Sn addition of 5%(mass fraction),which is attributed to the formation of refined β-Sn and primary ε-CuZn_5 phases in η-Zn matrix.However,when the content of Sn exceeds 5%,the shear strength decreases due to the formation of coarse β-Sn phase,which is net-shaped presented at the grain boundary.
采用DSC、SEM和XRD等方法,研究Sn含量对新型Zn-Cu-Bi-Sn高温软钎料组织和性能的影响。结果表明:添加Sn可以明显降低钎料的固、液相线温度和熔化温度范围,并显著提高钎料的润湿性能。对钎料的显微组织分析发现,当Sn含量为5%时,钎料的显微组织由均匀分布的细小β-Sn和初生ε-CuZn_5相组成;此时,接头剪切强度达到最大。进一步增加钎料含Sn量,组织中出现大量粗化的网状β-Sn相,钎焊接头强度降低。
基金
Project(20115003)supported by the Program for the Development of Science and Technology of Jilin Province,China
