无铅钎料的超电势问题研究

A Study on Over-potential of Some Lead-free Solders

通过对几种典型无铅钎料的电化学性能的研究，提出了无铅 钎料研究开发及应用时 应考虑因其超电势变化带来的影响问题。试验证明，含铋元素无铅钎料较传统的锡铅钎料超电势低，含铟无素无铅钎料则较锡铅钎料有较高的超电势，并证明这是由 于合金中形成了 Ｉｎ Ｓｎ４ 化合物的缘故，从 而认为含铋无铅钎料应谨慎地使用于电器元件的焊接生产中，而含铟无铅钎料 则较锡铅钎料具有更高 的电化学安全性，在电器元件的焊接生产中具有良好的应用前景。

Through the study of electrochemical performance of several lead-free solders, it is clear that the influence of over-potential variety on lead-free solders must be taken into consideration when developing and applying them. It has been found that lead-free solders with Bi have lower over-potentials, while lead-free solders with In which attributes to the formation of InSn 4 in alloys have higher over-potentials compared with conventional Tin-Lead solders. Therefore,lead-free solders with Bi must be considered carefully, while lead-free solders with In have higher electrochemical safety when they are applied in welding electrical apparatus. So lead-free solders with In may have good prospects for electronic devices.