The lead‑tin solder has already been replaced by the lead-free solder gradually in most industrial applications according to the RoHS restriction. However, the reliability test duration and the failure mechanism of lead-free solders are always a concerned problem that must be addressed when designing a new electronic product. In this paper, a thermo-electric accelerated test (TEC) method, as well as its corresponding failure mechanism, was discussed to consider the feasibility of reducing the reliability test duration. Compared with the traditional thermal cycling (TC) test, the lifetime of the component boards decreased apparently in the thermo-electric accelerated test, including both the time-to-failure and the cycles-to-failure based on the Weibull distribution. The main failure mode in TEC test is the cracks propagating along the boundaries of the recrystallized grains at the corner of a solder joint, similar as the TC test. The higher acceleration rate of TEC test might be related to the intermetallic evolution both at the interface and in the solder bulk. Thus, it could be concluded that the thermo-electric test would be a valuable option to achieve highly accelerated reliability test for electronic products.

根据RoHS限制，在大多数工业应用中，铅锡焊料已逐渐被无铅焊料取代。但是，无铅焊料的可靠性测试持续时间和失效机理始终是设计新的电子产品时必须解决的问题。本文讨论了一种热电加速测试（TEC）方法及其相应的故障机理，以考虑减少可靠性测试持续时间的可行性。与传统的热循环（TC）测试相比，在热电加速测试中，组件板的寿命明显缩短，包括基于Weibull分布的失效时间和失效周期。TEC测试中的主要失效模式是裂纹在焊点拐角处沿着再结晶晶粒的边界传播，这与TC测试类似。TEC测试的较高加速速率可能与界面和焊锡块中的金属间演变有关。因此，可以得出结论，热电测试将是实现电子产品高度加速可靠性测试的有价值的选择。