【摘要】 研究了Sn-58Bi共晶焊料与Cu的界面反应以及在Cu基体上化学镀Ni-P层的界面反应.焊接温度为180℃,焊接后时效温度范围为60-120℃,时间为5-30 d.利用SEM,EDAX,XRD对反应产物进行了鉴定.结果表明,焊料与Cu的界面反应产物为Cu6Sn5,与化学镀Ni-P层的界面反应产物为Ni3Sn4,在Ni3Sn4与Ni-P层之间存在一层富P层.在同样条件下,Cu6Sn5的生长速度要快于Ni3Sn4的速度.化学镀Ni-P层中P含量较高时进一步抑制Ni/Sn界面反应生成Ni3Sn4的速度.界面金属间化合物层生长动力学符合x=(kt)1/2关系,表明界面反应由扩散机制控制.由实验结果计算,Cu6Sn5的表观激活能为90.87 kJ/mol;Ni3Sn4的表观激活能则与化学镀Ni-P层中P含量有关,当镀层P含量为9％与16％(原子分数)时,其表观激活能分别是101.43 kJ/mol与117.31 kJ/mol.更多还原

【Abstract】 Interfacial reactions between eutectic Sn-58Bi lead-free solder and Cu or electroless Ni-P plating were studied. The joining temperature was 180 ℃, the aging temperature was 60 -120 f33, and the aging time was 5 to 30 d. The interfacial reaction products determined by SEM, EDAX and XRD are Cu6Sn5 on the solder/Cu interface, and Ni3Sn4 on the solder/Ni-P interface. In addition, there is a P-rich layer between Ni3Sn4 and Ni layer. The growth rate of Cu6Sn5 is much faster than that of Ni3Sn4. The growth rate of Ni3Sn4 was found to decrease with increasing P content in the electroless Ni-P plating. The kinetics of the intermetallic compound growth follows a parabolic law of time, as controlled by the diffusion mechanism. The apparent activation energies are 90.87 kJ/mol for the growth of Cu6Sn5, 101.43 kJ/mol for Ni3Sn4 on Ni-9%P plating and 117.31 kJ/mol for Ni3Sn4 on Ni-16%P plate, respectively.更多还原