表面安装技术 表面安装焊点的环境和耐久性测试方法 第1-5部分：机械剪切疲劳测试（1.0 版）

[中文适用范围]： 本部分IEC 62137描述的测试方法适用于面积阵列封装，如BGA。该测试方法旨在评估如图1所示的在组件引脚与基板焊盘之间的焊点的疲劳寿命。通常采用温度循环方法来评估焊点的可靠性。另一种方法是对焊点进行机械循环，以缩短测试时间，而不是通过改变温度产生应变。该方法是通过机械位移对焊点施加剪切变形，而不是由CTE（热膨胀系数）不匹配产生的相对位移，如图2所示。代替温度循环测试，机械剪切疲劳通过机械循环焊点来预测焊点在重复温度变化条件下的可靠性。在本测试方法中，评估首先需要将表面贴装组件通过回流焊安装在基板上，然后对焊点施加循环机械剪切变形，直到焊点断裂。评估焊点的特性（例如焊料合金、基板、安装设备或设计等），以帮助提高焊点的强度。注：然而，本测试不测量电子组件的强度。评估焊点对基板的鲁棒性的测试方法在IEC 60068-2-21中描述。 [外文原描述]： IEC 62137-1-5:2009 applies to area array packages, such as BGA. This test method is designed to evaluate the fatigue life of the solder joints between component leads and lands on a substrate as shown in Figure 1. A temperature cyclic approach is generally used to evaluate the reliability of solder joints. Another method is to mechanically cycle the solder joints to shorten the testing time rather than to produce the strains by changing temperatures. The methodology is the imposition of shear deformation on the solder joints by mechanical displacement instead of relative displacement generated by CTE (coefficient of thermal expansion) mismatch, as shown in Figure 2. In place of the temperature cycle test, the mechanical shear fatigue predicts the reliability of the solder joints under repeated temperature change conditions by mechanically cycling the solder joints. In this test method, the evaluation requires first to mount the surface mount component on the substrate by reflow soldering, then cyclic mechanical shear deformation is applied to the solder joints until fracture of the solder joints occurs. The properties of the solder joints (for example solder alloy, substrate, mounted device or design, etc.) are evaluated to assist in improving the strength of the solder joints.