采用声发射技术监测了焊接梁疲劳试验的过程，准确地监测到了焊缝和应力集中部位处的裂纹萌生及扩展．根据累积声发射振铃计数与时间的关系曲线定义了焊接梁损伤的三个阶段，并在此基础上提出了描述材料疲劳累积损伤的模型． Acoustic emission technology was used to monitor the fatigue test of welded beams and accurately detect the initiation and propagation of cracks at the weld and stress concentration sites. According to the curve of accumulated acoustic emission ring count and time, the three stages of the damage of the welded beam are defined, and on the basis of this, a model describing the cumulative fatigue damage of the material is proposed.