基于电阻应变的无铅焊点损伤临界点在线检测

Detection Damage on Critical Point of Lead-free Solder Joint Based on Resistance Strain

蠕变损伤是引起焊点失效的重要因素,传统的蠕变测试方法不能实时的测得无铅焊点的蠕变损伤临界点。研究表明,焊点的蠕变损伤与其电阻变化存在着线性关系。本文利用特制的无铅焊点微电阻在线测量系统,实时监测焊点在蠕变过程中的电阻变化,并利用二次移动平均法建立焊点电阻的预测模型,通过对比预测电阻值与实测值的差异,实时判断出焊点的损伤临界点,为蠕变测试研究提供了一种新的方法。

The damage caused by creep is an important factor in the failure of solder joints.It is difficult to detect the damage critical point in creep process by traditional methods in real-time test.The experiment results show that there is linear relationship between the solder joint creep damage and its resistance changes.An electronic testing system was set up to test the resistance of solder joint in creep process.Then,a forecasting model for the resistance was established by double moving average method,the predicted value was compared with the measured value,and then the damage critical point can be identified in real-time test.This provides a new approach for the creep study of solder joint.