采用常规的无损检测手段检测装甲车辆悬挂系统扭杆裂纹损伤比较困难。为了方便地检测扭力轴上的裂纹缺陷，提出了利用声发射技术在扭杆加载状态下，检测裂纹损伤的方法。为此基于虚拟仪器的原理，采用便携式工控机、高速数据采集卡、高灵敏传感器、手动液压加载装置构建了扭杆检测硬件系统，并编制了专用的检测定位软件。通过实际应用试验，成功地检测到了被测装备扭杆上的损伤。通过对比分析可得，基于声发射技术的动态检测方法是解决扭杆裂纹静态检测的有效办法。

It is very difficult to detect the crack of torsion bar of armored vehicles suspension system by ordinary nondestructive testing method. In order to detect the crack damage of torsion bar expediently, the method for crack detecting by AE technique under loading condition was given. Based on the principle of virtual instrument, a detecting hardware system was built, using the devices, such as portable industrial control computer, data acquisition card, high sensitive sensors and manual hydraulic loading device. Also, appropriate detecting and locating software system were programmed. The studying process and the nondestructive detecting system built for this study were summarized and analyzed. The crack of torsion bar tested was detected successfully in the experiment on real equipment. And the following result can be found out: the dynamic detecting method based on AE technique is an effectual method to solve the problem that is difficult to detect crack damage of torsion bar under static condition.